How the FED works and what purposes it serves

Take a look around the website of the Federal Reserve: https://www.federalreserve.gov/aboutthefed.htm
Explain how the FED works and what purposes it serves?
What’s the Fed doing to respond to the COVID-19 crisis?
Explain what is meant by the FED’s dual mandate?
The following website is for your reference or you can find the information on Fed official website.
https://www.brookings.edu/research/fed-response-to-covid