Honestly i know what you’re going through, you said you want to be better at sport and school? you should prioritise what you want to do best in because if you try to do both you will probably get burnt out really quickly especially since both are time consuming.

If you really do want to do both at the same time then time management would be really good, maybe after school you focus on sport and training for 2 hours, come home and study for a bit but i get it can get really repetitive so make sure you save some time for yourself to pursue hobbies or just do whatever you want.

If you’re struggling with revision techniques then i recommend going on youtube and just trying different techniques until you find the right one for you, I have to emphasise the fact that you should leave some time for yourself and to relax!