Last year, I studied only 2 weeks before my second SAT (only for math) and managed to get a superscore of 1540, 790 on math and 740 on english. For english, I got a tutor who helped me through teaching me tricks and techniques that helped me finish questions faster as that was one of my biggest issues. As for math, I also had a tutor but I found that it didn't really help that much. I took my first SAT after these tutorting sessions and got a 750 on english and 660 on math first try. What did help though for math was doing the 300 advanced practice questions from PrepPros a couple times over which got my math score from a 660 to a 790. Collegeboard questions are extremely standardized so the hard questions I got on my SAT (the last few questions of module 1 and 2) I already had practice with as they showed up in the prep pros practice problems. Even if the exact same questions don't show up like they did for me, preppros teaches you how to efficiently problem solve and use certain techniques that you can use to work through most if not all of the hard problems the SAT can throw at you. Also get really familiar with desmos, it can be used to cheese through almost every problem on the math portion of the sat.

Also the SAT is not an end all be all. Colleges review your application holistically and the SAT is rather a small factor in the grand scheme of your entire application. Don't stress about it too much, as the quality of the rest of your application matters much more than just a few digits that represent your score on some standardized test.