Hi

If you are still in your class 11 then you cannot attempt JEE Mains examination this year but yes you can attempt it next year while appearing for your class 12th board examination.

Coming to books , actually the syllabus of state boards is different and it varies from one state to other. So state boards books/syllabus are not recommended for JEE mains preparation as Jee mains doesn't follow your state board syllabus , jee mains syllabus is basically the syllabus of ncert of class 11th and 12th for physics chemistry and maths.

So, yes you should read NCERT for your JEE mains preparation , in addition to NCERT you need to follow other books as well as ncert doesn't have enough number of MCQs to practice but in JEE Mains mcq question and  numerical value type questions are asked so you need to practice them so you need to follow other books as well.

The top books which you can follow for the preparation of your JEE  examination  are provided below:-

CHEMISTRY :-

NCERT Textbooks - Class XI and XII :- master it as many times questions have been  directly asked from NCERT

*Modern Approach to Chemical Calculations by R.C. Mukherjee:- best for practicing numericals in physical chemistry

*Organic Chemistry by O P Tandon:- best for clearing all your doubts in organic chemistry

*Concise Inorganic Chemistry by J D Lee:- Best for your inorganic chemistry.

PHYSICS

*Concepts of physics Vol I and II by HC Verma
*Problems in General Physics by I.E Irodov
*Objective questions on physics by DC Pandey

Mathematics :

*Maths XI and XII by RD Sharma
*Complete mathematics by TMH
*New pattern mathematics for JEE by Arihant publications

Also go through previous year jee mains chapter wise question book for each of physics , chemistry and Mathematics . Solving previous year questions will let you know the type and difficulty level of questions etc, will let you know your preparation level and and weak areas so that you can work on them .

For detailed information go through

https://engineering.careers360.com/articles/best-books-for-jee-main/amp

Thank you