The Senate is made of 1 of 2 chambers; It is part of the legislative branch, and hold unique power. Usually the Senate is made up of what we would call ‘elders’
The House of Representatives is 1 of 2 chambers ( or 2 of 2 lol ) and is part of the legislative branch. They make and pass federal laws.
The Senate can do two thing the HOR cannot; ratify treaties and veto (reject lol) presidential appointments. So they are in a sense more powerful