Billions of dollars in aid hang in the balance, just as the government is running low on money for additional booster doses and a highly contagious new subvariant looms.WASHINGTON — President Biden stepped up pressure on Congress to approve billions of dollars in emergency coronavirus relief aid, using a speech at the White House on Wednesday to warn that U.S. progress against Covid-19 would be at severe risk if Congress failed to act right away.“This isn’t partisan. It’s medicine,” Mr. Biden said, adding, “Americans are back to living their lives again; we can’t surrender that now. Congress, please act. You have to act immediately.”On Capitol Hill, senators of both parties said they hoped a deal could be struck before Congress leaves next week for a two-week April recess. Such a deal would likely be $15.6 billion, matching the size of the smaller package that Democrats abruptly removed from a catchall spending bill earlier this month when rank-and-file lawmakers and governors objected to clawing back state aid to help pay for the deal.It remains unclear how the package will be paid for — a Republican demand that has delayed passage.“It’s totally up to Democrats,” said Senator John Thune of South Dakota, the No. 2 Republican. “This can get done, but it’s in their court, and it just requires them to be willing to repurpose some existing funds, which they’re reluctant to do.”Mr. Biden’s speech on Wednesday was his first dedicated entirely to the pandemic since before his State of the Union address on March 1. It came just one day after federal regulators cleared additional boosters of the Pfizer and Moderna vaccines for Americans older than 50 and many immunocompromised people, four months after their first booster dose.At the end of his remarks, the president, 79, rolled up his sleeve to get his second Pfizer-BioNTech booster shot.Mr. Biden also used his remarks to spotlight a new one-stop-shopping coronavirus website, covid.gov, aimed at helping Americans navigate access to testing, treatment, vaccines and masks, and to assess the risk of Covid-19 in their neighborhoods. The site went live Wednesday morning.The website, and Mr. Biden’s speech, are part of a broader effort to ease the nation out of pandemic crisis mode and usher in what experts are calling the “next normal” — a phase in which Americans will learn to live with the risk of Covid-19 and to adjust behavior like wearing masks based on whether cases and hospitalizations are rising or falling.That strategy depends on the availability of vaccines and therapeutics, though, and the administration says it is out of money for both. The White House has been pleading with Republicans in Congress to approve the emergency aid to purchase new vaccines and therapeutics, and to reimburse doctors who care for uninsured Covid-19 patients.The federal government said recently that a fund established to reimburse doctors and hospitals was no longer accepting those claims for virus testing and treatment “due to lack of sufficient funds.”While new coronavirus case have been falling in the United States, a highly transmissible Omicron subvariant known as BA.2 has driven a surge in cases in Europe, and many experts expect that the United States may soon see the same. Should that occur, it will be the first major test of the country’s new strategy of living with the virus while limiting its impact.Around the country, state and local governments have relaxed restrictions like mask and vaccine mandates. White House and federal health officials have been making the case for weeks that Americans now have the tools — testing infrastructure, masks and other mitigation strategies, and drugs and vaccines — to live with the threat of the virus.In his State of the Union address, Mr. Biden announced a new “test-to-treat” initiative — a network of pharmacies and other sites where people can be tested for the coronavirus and then receive antiviral drugs if they test positive. More than 2,000 sites are participating, the White House said. The covid.gov website features a tool to help people find participating locations.Under a banner saying “Find Covid-19 guidance for your community,” the website asks users to enter the name of the county in which they live. It then identifies whether the risk of Covid-19 in that county is low, medium or high, depending on factors including the number of hospitalizations and available hospital beds.The site also links to other government websites, including vaccines.gov and covidtests.gov, that help users access vaccines and find nearby testing sites.At a House hearing on Wednesday, Dawn O’Connell, the assistant secretary for preparedness and response, said that over 900 million of the billion at-home rapid tests President Biden had promised to offer Americans for free had been secured, and that over 250 million “high quality” masks, including the N95 style, had been shipped across the country.But she warned that the administration was so low on funds that it was unclear if the federal government would have enough money to purchase enough second booster doses, if the general public eventually needs them, “particularly if we are going to need a variant-specific vaccine.”On the other side of the Capitol, Senator Mitt Romney, Republican of Utah, who has been leading talks with Senator Chuck Schumer of New York, the majority leader, emerged from an afternoon meeting with Mr. Schumer and other top lawmakers on Wednesday and said the two parties had exchanged lists of possible funds to repurpose, but had yet to reach agreement.“There’s a gap between where we would go and where they would go,” Mr. Romney told reporters on Capitol Hill.Speaking on the Senate floor ahead of the meeting, Mr. Schumer warned that “the consequences of not getting Covid funding are really serious — scary, almost.”“We are not yet at the finish line,” Mr. Schumer said, “but we will keep working throughout the day and I am committed to working with the other side reasonably and in good faith.”