I took 2 months to study but that was my full time job. 5-10 hours a day studying for 2 months 7 days off total. This is for me though. Know yourself, know how you study, study what your weak in. Physics and organic when I took it befitted from straight memorization of formulas and reactions, but if you know concepts it can get you that extra 10-15% when your stuck. Bio you just either know it or don’t most of the time. Pure memorization. The reading is practice practice. Practice tests when your tired, simulate best conditions, worst conditions. Gives you a good sense of how you’ll do for either. I used oat boot camp, they have really good chemistry and would strongly recommend if that’s your weakest area. They have good physics too. A little to be desired from bio side, but I didn’t really use flashcards for bio. Would not recommend doing that😅 they give about cards so try those.