The first full week of the Biden presidency has unfolded with a certain rhythm, with each day putting a spotlight on a new policy theme. President Biden has addressed American manufacturing, racial equity and climate change since Monday.

Thursday is health care day.

In the afternoon, Mr. Biden is scheduled to sign executive actions, including one that will reopen enrollment in many of the Affordable Care Act marketplaces so that Americans without health coverage can sign up — a move intended in part to help those who lost coverage during the coronavirus pandemic.

The themed days are a way the new president and his team draw attention to the White House’s early priorities. And after a campaign in which Republicans sought to portray Mr. Biden as a sedentary figure confined to his basement, the daily appearances — and the flurry of executive orders — show him taking swift action in a variety of areas.

Among the actions slated for Thursday is reinstating global protections for women’s reproductive health care by eliminating the rule that prohibited the granting of American foreign aid to health providers abroad that offer abortion counseling. The Trump administration reinstated this Reagan-era policy, and the Biden administration is reversing it.

On Wednesday, he signed a series of executive actions related to climate change and science, and two top officials working on climate issues, John F. Kerry and Gina McCarthy, appeared at the daily White House briefing to discuss the subject with journalists.

But there are limits to what Mr. Biden can do by himself through executive action, and Thursday’s health care actions are no exception.

The step of reopening Obamacare marketplaces is a small and temporary one in the context of the president’s overall agenda, which calls for bolstering the Affordable Care Act and creating an optional government health plan that consumers can purchase, known as a public option.

To realize his full vision on health care, Mr. Biden will need Congress to take action. And past battles on Capitol Hill — including the failed effort in the first year of President Donald J. Trump’s administration to repeal the Affordable Care Act — have proved just how difficult it can be to pass far-reaching health care legislation.

Eileen Sullivan contributed reporting.

The Biden administration plans to reopen enrollment in many of the Affordable Care Act marketplaces, both to help those who may have lost health insurance during the pandemic and to offer coverage to those who did not have any and now want it.

The White House announced Thursday that President Biden would sign an executive order describing the administration’s policies on shoring up health insurance coverage.

The so-called special enrollment period is intended to help people who have lost coverage in the past year, but it will be open to those who want health insurance for any reason in the 36 states that use Healthcare.gov. The decision was reported earlier by The Washington Post.

Typically, Americans without a special circumstance can only buy insurance through the Affordable Care Act, also known as Obamacare, during a six-week period in the fall, a restriction meant to encourage people to hold coverage even when they are healthy. The sign-up period for this year’s coverage ended in mid-December, with enrollments only slightly higher than they were last year. But the Trump administration did little to advertise it. The Biden administration plans to have a large marketing campaign to announce the new opportunity and encourage people to enroll in health plans, according to two people familiar with the details.

The insurance industry, which usually supports tight limits on insurance enrollments, is backing the extra enrollment period now. Around 15 million Americans are uninsured and eligible for marketplace coverage, according to a recent analysis from the Kaiser Family Foundation. Most would qualify for some form of financial assistance if they bought such coverage — and about four million could sign up for a high-deductible plan that would cost them nothing in premiums.

“For the four million people who could be getting free coverage who are instead uninsured — that, to me, is screaming out for outreach,” said Cynthia Cox, a vice president at the foundation and an author of the analysis.

It remains unclear how many people lost health insurance last year because of the pandemic, but most working-age Americans receive coverage through their employers, and millions have lost jobs.

Enrollment in Medicaid, the public health insurance program for the poor and disabled, has grown substantially during the pandemic. And consumer advocates say there are also many Americans who were uninsured before but might want coverage now because of the public health crisis. Several states that run their own marketplaces established special enrollment periods last year and reported increased sign-ups.

Video

Cecilia Rouse, a Princeton University economist who is President Biden’s pick to lead the White House Council of Economic Advisers, will tell a Senate committee this morning that Congress “must take action” to shore up an economic recovery that has left many Americans behind.

“As deeply distressing as this pandemic and economic fallout have been,” she will say, “it is also an opportunity to rebuild the economy better than it was before — making it work for everyone by increasing the availability of fulfilling jobs and leaving no one vulnerable to falling through the cracks.”

In remarks prepared for delivery at a nomination hearing before the Senate Banking Committee, Ms. Rouse also plans to say that if confirmed, she will make it a priority for the council to gather more detailed data, in order to better see how economic policies are affecting nonwhite Americans in particular.

“Too often economists focus on average outcomes, instead of examining a range of outcomes,” she will say. “As a result, our analyses tell us about average economic growth and the middle of the distribution — but as our economy grows more and more unequal, that analysis fails to capture the experience of the many people who are left behind, particularly people of color.”

Ms. Rouse is a labor economist whose work includes a longtime focus on education and discrimination. If confirmed, she would be the first Black economist ever to chair the council. She previously served as a council member under former President Barack Obama.

Her testimony comes at a precarious moment in the economic recovery from the pandemic and she is likely to face questions about the $1.9 trillion stimulus package that Mr. Biden has proposed to help get the virus under control and aid struggling families and workers.

Data released on Thursday morning showed that the economic recovery stumbled but didn’t collapse at the end of last year and that it could have a strong rebound in 2021 once the virus is arrested. Gross domestic product rose 1 percent in the final three months of 2020, the Commerce Department said Thursday.

Republicans have already expressed skepticism about whether the economy needs a $1.9 trillion jolt given the $900 billion stimulus package that Congress passed in December. But with millions still out of work and the virus not yet under control, many economists say workers and businesses will need more help to make it through.

Gov. Gretchen Whitmer of Michigan opened her annual State of the State speech on Wednesday by pleading with lawmakers to find common ground in fighting the staggering effects of the coronavirus pandemic in the state.

“Based on the political environment this past year, you might think Republicans and Democrats in Lansing can’t find common ground on much of anything,” said Ms. Whitmer, a Democrat. She noted times when there had been bipartisan action in the Capitol. “Let’s tap into that same energy and end the pandemic, revitalize our economy and get our kids back in school.”

But Republicans were having none of it.

Hours before Ms. Whitmer gave her speech, Republicans in the State Senate refused to approve 13 appointments she had proposed for slots in state government, such as the leader of the Children’s Ombudsman Office, the Civil Rights Commission and members of agriculture boards.

Republicans said they had rejected the appointments because Ms. Whitmer was not including them enough in decision-making surrounding restrictions on businesses to stop the spread of Covid-19.

“She has continued to circumvent the Legislature,” said State Senator Aric Nesbitt, a Republican from Lawton. “I understand it’s not easy to compromise and try to work with 148 members of this Legislature. We have to use every tool available to compromise, and one of those tools is to not support her appointments.”

Republicans in the State House of Representatives followed suit, offering a Covid-19 relief plan that would withhold $2.1 billion in federal funding meant to help schools cope with the pandemic until Ms. Whitmer relinquished her authority to shut down in-person learning and sports during a health crisis. That power would shift to local health departments under the Republican plan.

The public — and pointed — rejections of the governor’s appointments and authority come as Ms. Whitmer is preparing to run for re-election in 2022. No top-tier Republican has come forward to challenge her.

Forced to speak remotely instead of in front of both chambers of the Legislature because of pandemic protocols, Ms. Whitmer offered plans to fix roads, provide extra hazard pay to teachers and allocate state resources to help residents who have lost their jobs during the pandemic find employment.

But it was the coronavirus, which has infected more than 600,000 Michigan residents and killed more than 15,000 since it was first reported in the state in March, that dominated her address.

Ms. Whitmer said she planned to start a statewide tour to encourage Michiganders, Republicans and Democrats alike, to try and find common ground as the state emerges from the pandemic. The tour is designed “to focus on what unites us, improve how we talk to each other,” she said. “My mission is to find common ground so we can emerge from this crisis stronger than ever.”

NEWS ANALYSIS

President Biden has moved swiftly in his first days to start carrying out his agenda, signing executive orders and outlining new actions. But his most significant move may in fact be a reaffirmation of an old stance: that the Senate should protect the filibuster, the 60-vote threshold that has for years stymied expansive legislation, including on issues he now seeks to address.

Progressive grumbling over the filibuster rose this week after Senator Mitch McConnell of Kentucky, the minority leader, initially refused to agree to basic operating rules for the chamber unless Democrats agreed to maintain the procedural tactic. But it remained just a grumble, reflecting progressives’ desire to avoid intraparty warfare early in Mr. Biden’s term and their belief, shared more widely in Washington, that his hand may eventually be forced.

“We have to recognize that the Senate has fundamentally changed from the time President Biden served,” said Senator Edward J. Markey of Massachusetts, a progressive who has endorsed eliminating the filibuster. “And it’s made it impossible to move forward on big issues.”

Whatever the liberal wing of the party may want, eliminating the filibuster requires the support of the entire Democratic caucus. And several moderate senators, like Joe Manchin III of West Virginia, remain staunchly in favor of keeping it.

Some progressives believe that Mr. Manchin and others may change their minds if Republicans obstruct the Democratic agenda. For their part, some moderates argue that the threat of eliminating the filibuster could force Republicans into legislative compromise. The minority party has often used the filibuster to thwart signature items of the majority party, and some Democrats fear that, without it, they would be powerless to stop Republicans the next time they control the Senate.

Mr. Biden’s commitment to keeping the Senate filibuster harks back to the policy debates that animated the Democratic presidential primary.

The logic was informed by years of congressional gridlock under former President Barack Obama and the magnitude of challenges facing the country: Big problems need big solutions, they argued, and the filibuster was a blockade to progress.

With the Senate split 50-50 between Democrats and Republicans, that could empower Mr. McConnell and a small cadre of moderate voices to block nearly any piece of legislation. It could doom Mr. Biden to the same fate as his Democratic presidential predecessor, who blamed Republican obstructionism for blocking a more robust liberal agenda.

Mr. Markey said he was confident that if Mr. Biden began to experience the same fate, he would come around.