How should I study for these SAT II subject tests?

I haven't taken AP Chem and I took Honors Chem in 10th grade and I'm going to be a senior. Few colleges I want to apply to want a science subject test. I took AP Physics B, but I struggled A LOT. Which should I take? Also I finished pre-calc and how should I study for Math level 2? Would it be recommended to take spanish subject test because I want to go into pre med and i just finished spanish 4? Thanks!