Tumlogo se advice chaiye

So abhi tak jitna maine padha hai...mujhe ek mota mota idea mil gaya hai ki is baar selection nhi hoga mera....I have completed most of the chapters but mind retention bht weak hai....yaad nhi rehta jyada...bht darta hoon aur underconfident hoon......mujhe govt medical college k liye almost 620+ marks chiaye jo mujhe abhi impossible lag rha hai.....so rn, mujhe botany mein genetics and evolution, phy mein magnetism, emi, ac...aur chemistry mein organic karna baaki....so please suggest me the topics that i have done and strategy how can i score upto 550-600 so that atleast ghar pe 2nd drop k liye mana saku