Hi,

Below are the easy chapters have high weightage in JEE main :-

1. Unit and Dimension. Errors.( scoring topic and fix questions)
2. Work power energy.
3. ROTATIONAL motion.
4. THERMODYNAMICS. (Not easy , but very Important)
5. SHM.
6. Waves.

For the chapters I mentioned above, a short,  simple advice for you would be - focusing on theory, clear your concepts and for making your concepts strong practice as many as questions as you can. You can clear your basic and much needed concepts by referring NCERT and for JEE level questions practice your modules or any reference book and make sure you go through through past year questions asked in mains from these chapters.

Remember - JEE is a test which judges your conceptual clarity not your power of mugging things up.

Hope this helps.

All the best.