There are a lot of term limit posts. Here is my proposed language for a constitutional amendment. It does change existing terms for congress but limits both representatives and senators to two terms. And it has a limit on the age someone can hold office. Yes I know it would have applied to Trump in the past election.
Members of congress and the senate are limited to 2 terms, 4 years in congress and 6 years in the senate. Anyone who has already served more than 8 years in congress or 12 years in the senate is not eligible for reelection. Anyone over the age of 72 is not eligible to run for federal office