Addressing the coronavirus pandemic, confronting the climate crisis and building public trust in science and technology will be among the Biden administration's key areas of focus, the president-elect said during a press briefing introducing four key members of his science team.

Building back the economy "to ensure prosperity is fully shared all across America" and ensuring the U.S. "leads the world in technologies and industries that the future" will also be a focus, Biden said Saturday during an address in Wilmington, Delaware.

Helping lead those initiatives will be Eric Lander, the presidential science advisor-designate, a position that for the first time will be a cabinet rank, Biden noted.

"I've always said that the Biden-Harris administration will lead with science and truth," Biden said. "We believe in both. This is how we're going to, God willing, overcome the pandemic and build our country back better than it was before. That's why for the first time in history, I'm going to be elevating the presidential science advisor to a Cabinet rank, because we think it's that important."

Frances Arnold and Maria Zuber will be at the helm of the first all-women team to lead the President’s Council of Advisors on Science and Technology.

Alondra Nelson will also be deputy director for science and society for the Office of Science and Technology Policy.

Dr. Francis Collins, who was not present at the event, will also continue in his role as director of the National Institutes of Health.Biden thanked him for "being willing to stay on," saying that it wasn't his original plan.

"I've known Dr. Collins for many years. I worked with him closely," Biden said, accling him "brilliant, a pioneer, a true leader."

"This is the most exciting announcement that I have gotten to make in the entire Cabinet," Biden said of his picks. "These are among the brightest, most dedicated people, not only in the country but the world."

MyPillow CEO Mike Lindell on Friday was pictured outside of the Oval Office with a document appearing to detail drastic actions just days away from Biden's inauguration. The pillow inventor, who previously called for “martial law” in a now-deleted tweet, confirmed to ABC News that he met with Trump and presented him with a separate document filled with theories regarding election hacking.

The theories are related to repeatedly discredited claims that Trump had actually won the election.

The photograph went viral on Twitter after users speculated the document showed mentions of “martial law” and the “insurrection act.” 

White House sources stressed that nothing Lindell presented was taken seriously nor would it be acted upon by administration officials.

In an interview with ABC News, Lindell, a fierce supporter of the president, said his meeting with Trump was brief ("it was real fast") and said White House lawyers who reviewed the documents after his meeting with the president seemed “disengaged” and “disinterested,” which he said was “disturbing.”

“There was no mention of martial law,” Lindell said regarding the document photographed by the Washington Post, which he claims comes from one of the attorneys he said he has hired to investigate election fraud but would not identify to ABC News. 

Another section of the notes appears to read, "Move Kash Patel to CIA Acting" and "Make clear this is China/Iran." Much of the notes are not visible in the photo.

When asked if he read that document, Lindell told ABC News, “I glanced at it.”

“I'm going to be honest. I read that -- I don't know the names. I don't understand half the stuff on there," Lindell said. "...I don't know the names on there. I think there were suggestions on who to move."

Lindell said the photographed document was just a part of the bigger packet he had brought to the White House, and that his main intention was to show the president an article that alleges multiple foreign countries hacked the 2020 U.S. election. He said during the brief time he had with the president, he spoke to him about this article.

-ABC News’ Will Steakin, Soorin Kim and John Santucci

Biden and Vice President-elect Kamala Harris will introduce key picks for their science team in Wilmington, Delaware, Saturday afternoon.

The picks are:

-Eric Lander: Nominee for director of the Office of Science and Technology Policy (OSTP) and presidential science advisor-designate.

-Alondra Nelson: OSTP deputy director for science and society

-Frances H. Arnold: Co-chair of the President’s Council of Advisors on Science and Technology (PCAST)

-Maria Zuber: Co-chair of the President’s Council of Advisors on Science and Technology (PCAST)

In a press release, the Biden transition team said the picks will help the Biden-Harris administration "confront some of the biggest crises and challenges of our time, from climate change and the impact of technology on society to pandemics, racial inequity, and the current historic economic downturn."

Biden has announced a new slate of nominations and staff at the Department of State. Many of the picks have ties to both Biden and former President Barack Obama.

The picks are:

-Wendy R. Sherman: Deputy secretary of state

-Brian P. McKeon: Deputy secretary for management and resources

-Bonnie Jenkins: Under secretary for arms control and international security affairs

-Victoria Nuland: Under secretary for political affairs

-Uzra Zeya: Under secretary for civilian security, democracy, and human rights

In a statement, the Biden transition team said these key nominations will help "build back better at the State Department, renew and reimagine American leadership to keep us safe at home and abroad, and address the defining challenges of our time — from infectious disease, to terrorism, China, nuclear proliferation, cyber threats, and climate change. They will put into practice the President-elect and Secretary-designate’s vision of a foreign policy that promotes America’s security, prosperity, and values, and delivers for the middle class."

-ABC News' Beatrice Peterson

Biden outlined the major points of his rescue plan: a $1.9 trillion proposal that includes a nationwide vaccination program, $1,400 checks for individuals, an extension and expansion of unemployment benefits and help for struggling communities and businesses.

Biden placed particular emphasis on housing and food insecurity and spoke about expanding SNAP benefits. He said his policy plan would extend the eviction and foreclosure moratorium, potentially previewing an executive action we could see next week. He also asked Congress to appropriate funds for rental assistance.

Biden, who preached bipartisanship while on the trail, said both he and Vice President-elect Harris had spoken with officials, mayors, and governors of both parties on a regular basis to address the problems across the country.

The president-elect also emphasized his plan's focus on helping small businesses and minority-owned businesses in particular, criticizing the Trump administration's initial approach which he said favored the wealthy and well-connected.

"Last week, I laid out how we'll make sure that our emergency small business relief is distributed swiftly and equitably, unlike the first time around. We're going to focus on small businesses, on Main Street. We'll focus on minority-owned small businesses, women-owned small businesses, and finally having equal access to the resources they need to reopen and to rebuild," Biden said.

He also pushed his plan for a mandatory federal minimum wage of $15 an hour.

"People tell me that's going to be hard to pass. Florida just passed it, as divided as that state is, they just passed it. The rest of the country is ready to move as well," he said. "No one working 40 hours a week should live below the poverty line. And that's what it means. If you work for less than $15 an hour and work 40 hours a week, you're living in poverty."

He frankly noted the "bold, practical" policy he was putting forward did not come cheap but argued there was no option to act.

"I know what I just described does not come cheaply. But failure to do so will cost us dearly," he said. "The consensus among leading economists is we simply cannot afford not to do what I'm proposing."

Biden ended his remarks with a call for unity and optimism, referencing his inauguration on Wednesday as a "new chapter for the country."

-ABC News' John Verhovek, Molly Nagle, Averi Harper and Beatrice Peterson