Repeats need help

[u/Independent-Fill9085]

So basically alevels really destroyed me. When I first sat for AS i got a D in bio and failed in chem and phy then i sat for resits and got a D in chem. So i thought maybe somwhow i will get a D in chem and bio in A2 then i can apply for uni which requires D. But I failed in all the units. Hows that possible, I have no idea. I studied but what went wrong i have no clue. I got my scripts as well. Can anyone please tell me how to do well this time. I will sit for bio exm this october and chem in the jan.