Many, but not all, four-year colleges in the US require or recommend the SAT (or ACT). The requirement varies widely depending on the college's admissions policies. Some colleges are "test-optional," meaning they don't require SAT/ACT scores for admission. Others are "test-blind," meaning they won't even consider your scores if you submit them. Still others require them.
To know for sure whether a specific college requires the SAT, you must check the admissions requirements on that college's website. There's no single answer; it depends entirely on the individual institution.