Genuine need for advice

I passed my 12 last year and started studying computer science in a realtively okay college but still there are alot of things that are quite noticable, ofcourse I will not name anything or anyone, and I will also not go in much deatil of this, but the simplest way to explain why I am having doubts about my college would be the follwing analogy: "yesterday, our teacher taught us how to use windows 7 while students were taking notes on windows 11" now my friend suggested that I can give JEE exam if I want a better college, and I did give the JEE mains exam during my 12th class without much focused preparation and barely scored 64 marks. The main problem is that my parents don't want me to do JEE and just want me to fucus on what is going on in college, so I don't have much money to buy a batch of any coaching but I can arrange books from my friends which gave their JEE atempts this year. Is it possible to crack JEE for a good college, while being in a collge, using only books and no coaching ? I know it's difficult and I am willing to work hard on it but I genuinely need some advice on how to achieve this. Any help is appreciated! Thank You!