All legislative Powers herein granted shall be vested in a Congress of the United States, which shall consist of a Senate and House of Representatives.Section 1 is simply stating that the legislative branch of government consists of a Senate and a House of Representatives which makes up a Congress and their powers are written in the US Constitution.
Senate = Each U.S. state is represented by two senators, regardless of population. Senators serve staggered six-year terms.
House of Representatives = Each state receives representation in the House in proportion to its population but is entitled to at least one representative. The total number of voting representatives is fixed by law at 435. Each representative serves for a two-year term. The Speaker of the House, traditionally the leader of the majority party, is the presiding officer of the chamber, elected by the members of the House.
I know is short, but I want to keep these short and sweet. Thanks for reading!