Hi, I’m a pre-ib sophomore right now, planning on taking those courses, and advice?
Anything I should do before hand to prepare for that as well as for Math SL, History of Americas and TOK?
Please please reply! I’d love to hear and prepare 
Thank you~
You can’t prepare for TOK. For maths SL, find the bit on presumed knowledge on the IB syllabus and ensure you know everything on there.
For biology/chemistry, there isn’t much you can do to be honest, perhaps read over the IB textbook.Can’t advice you on history as I don’t take it.
I honestly don’t recommend you do anything, relax now and start studying for those classes once your in IB. Take full advantage of your free time by preparing for PSAT, SAT/ACT and SAT II instead.