Dear Monika ,
Really good decision from your side to prepare for IIT-JEE. you have a lot of time to grasp concepts and build yourself . Start reading NCERT books seriouisly , they need to be solved thouroughly. As far as other books for PCM are concerned ,
PHYSICS , read and solve H.C verma, it will clear concepts.
MATHS , solve R.D Sharma whcih has got lot of problems to solve .
Chemistry ,take a book by S.chand , they are good.
ALso as a suggestion i will suggest that you should give olympiad exams as they are ultimate testing points at your level.
GOOD LUCK !!!!
Please feel free to post as many doubts on our discussion forum as you can. We are all IITians and here to help you in your IIT JEE preparation.
Now you can win exciting gifts by answering the questions on Discussion Forum. So help discuss any query on askiitians forum and become an Elite Expert League askiitian.