Help needed

hello, ill be retaking my physics and maths as levels in oct/nov. since ive done poorly on both subjects, i need to relearn the courses all by myself. does anyone have any tips since i have no idea how to start and where from. i failed physics, and got a d/borderline c in math. obviously i need to start from scratch with phy, however i completely understand like 90% of maths, i just severely lack practice (also confirmed by my teacher and tutor). thank youu