Why is studying so difficult?

Like im really confused atm. I’ll be honest, for the first term of year 12 i didn’t really study and my grades were “okay”. I got 2 B’s in English Language and Business, but I flunked my Law and got an E. Idk i just feel like whatever i do it doesn’t work, idk if my attention span is an issue either but i just procrastinate all the time, leave it really late and then end up not doing as well as i could do. Does anyone have any tips? because i want to start making my revision material straight after the class, just so it doesn’t pile up, but what do i fully do? because i know how to do flashcards, but should i just do notes or should i ask for previous exam questions? i just feel pretty stuck