Any college you apply to will require you to submit an SAT or ACT score, so they will definitely take a look at it. Colleges use the SAT to help them make admissions decisions because it gives them an even playing field from which to evaluate students.

GPA is an effective rubric for evaluating students, but there are a lot of differences in GPAs between schools. Some are harder, some are easier, some have more AP classes than others. All in all, it's not the best thing to judge someone by. So they use the SAT because it's the same everywhere.

don't worry if your SAT score is not great at first. you can take it a bunch of times, and your score will improve over time, especially if you study for it and use your prepme. schools will look at your best scores, so set your sights on the next test!