Check out what parentologist suggested - you may be able to repeat a year in high school. That is a frequent solution for teenagers who move from one educational system to another, and for now, it would be the easiest and cheapest solution.
You may, at some point in time, be able to excel in the US system and get great grades and test scores. But that point in time isn’t now, because you are still learning and adjusting. And that’s okay, it’s not your fault, it’s just how your life worked out. You have all the opportunities of the U.S. of A. at your fingertips - but you can’t quite profit from them yet.
Your teacher may have stressed the importance of SATs because colleges in the US may not really know what to make of your high school record, with two years’ worth of Turkish grades and one semester’s worth of US grades, which probably will reflect your struggle to learn English and adjust. But if you feel you would struggle with the SATs as well at this point, they would not help your college application either, and you would probably not be very successful if you tried to apply to 4 year colleges this fall.
Take your time. You may be able to repeat a year in high school. You can live with your family and go to community college, full time or part time, and work to support yourself, and improve your English. And when you’re ready, move on to a four year university and continue to do your best.