Goc helpp

I have been trying for 1-2 weeks now to try and crack goc but I cant understand it.i go through theory and stuff and i get it but when I open my tuition book to solve questions im blank.Even during coaching I understood the shit.

What can I do cuz I rlly dont wanna cont wasting time like this but I need to do goc properly or ill ruin my oc completely.

How did ull study goc?