a level chem+bio help

hi
im doing exam past papers for AS for chem and biology but the problem is that i literally am struggling to identify my weak points..
like when its a question based on a normal topic - ex: kc hess law atomic structure enthalpy calcs practicals etc im calm and get it mostly right. but when its like an application (esp bio) or some random chem queastion i just struggle to get it and i feel like its hard to revise that stuff as its not just in a yt vid or a textbook.. how am i supposed to improve on these as for like chem im barely getting 60% so around a B when i really need an A or A*.. likewise with bio.. its worse in chemistry though as grade boundaries are lower for biology.

any help on just dealing with those sort of random questions in chem especially and biology will be greatly appreciated as i feel like when i review a past paper i dont even know how to practice the stuff i got wrong as u cant just find it online..
thanks..

I’d be inclined to keep a folder of the questions you get wrong, along with a record of the mark schemes and just do the questions again every once in a while until you consistently score every mark.

You could even make flashcards out of these questions if you so wish and try to apply the ‘Leitner system’ if you so choose.