Hello aspirant

Hope you are doing great there . JEE mains is a national level exam and therefore to maintain its decorum , it relates most of its syllabus to CBSE that is Central Board Of Secondary Education . Therefore I would suggest you to check the jee mains syllabus from the official site of NTA . Also if some part of JEE mains is missing in your respective board , then you can cover that particular topic from you tube or your respective coaching centre will help you for the same.

I hope my answer helps

Wish you all the very best!