hi, Ruby
the framers of our nation, in the US Constitution, gave us a bicameral federal legislative branch.
that's smart guy fancy talk for two chambers of lawmakers, lol
in the House of Representatives the members serve two year terms, thus all are elected every two years.
in the Senate the members serve six year terms, and one third are up for reelection every two years.
you're correct! the president serves a four year term. he or she may only serve two terms, and Mr Biden, who was elected in 2020, is in office till the next 'major' election in 2024.
we call these elections this year, the midterms because they're held in the middle of the president's term of service.
clears it right up, eh?