What are the benefits to having a president that is of the same party as the majority group in both the House and the Senate? What are the challenges when the President's Party is not the
Majority party in the House and the Senate?

The benefits are that it is easier for congress to pass legislation because if both majorities are the same party as the president, they will agree on most of the same issues.

the challenges is that it could make the president look like they didn’t do anything while in office, because they did not agree with the legislation put forth by congress.
for example, say the majority of the senate and house of representatives is republican, but the president is in the democratic party. the president would most likely not agree with any of the bills put on their desk by congress, so they would veto it, making the president look bad and harder for them to pass any laws.
hope this helps! :)

The dangers of an inadequate monetary supply.