There are several study materials available but you need to stick to few books and do them several times rather than several books once

I can suggest you these for your help

Important books for JEE MAIN

For Physics-

• Concepts of Physics Vol I and II by H.C. Verma
• Problems in General Physics by I.E. Irodov
• Fundamentals of Physics by Halliday, Resnick & Walker

For chemistry-

• Numerical Chemistry by P. Bahadur
• Organic Chemistry by Paula Bruice Yurkanis
• Inorganic Chemistry by J.D. Lee
• Organic Chemistry by Morrison & Boyd

For mathematics-

• Maths XI & XII by NCERT (
• Trigonometry by S. L. Loney
• Co-ordinate Geometry by S. L. Loney
• Higher Algebra by Hall & Knight
• Problems in Calculus of One Variable by I.A. Maron

NCERT is a basic must for the subjects.

Understand the concepts and do numerous problems on it and I would you to stop checking internet for trivial questions like- How to study for jee main and what is the best book-

You need to understand that everyone who cracked this exam had a unique approach and there is nothing like best book for any exam. You just need to keep giving several mock tests as well as previous year paper

Hope this helps !

All the best