Dear Aspirant,

Study all the concepts, and once you have found something difficult to understand use some external resources like Help books, or online explanations. The examples in NCERT are very very important for competitive exams as they are sometimes directly asked in the JEE with slight changes.

For physics, also try to solve the exercise questions as they have really good questions and once again you should use some external sources for this.

For chemsistry, do give NCERT a read in the last month of your preparation as there are many inline text questions in JEE main from there.

Hope this helps. Thank you.