Hi

Greetings.

Go through Chemistry NCERT line by line and remember all the content because most of the questions in chemistry section will directly come from NCERT next comes don't read any new concept work to strengthen the concepts in which you are strong because if you read any concept then it will not get you anymore because the questions will be not simple formula based and require a good knowledge of concept so the concepts in which you are stronger in physics and mathematics you need to work on them and make them is stronger so that you don't miss the questions which come from them.

while attempting JEE main question paper  solved questions just mark those questions in which you are comfortable and solve them so that your accuracy  100% and  you don't go for any negative marks

All the best