Hello,
You need to read only your textbook and have to practice questions from your textbook.You must solve previous years questions for practice and to enhance your skills because questions are mostly repeated in exams.You have to analyse your strength and weakness...and have to work on weak areas.You have to be confident and don't take stress.
All the best.

Dear Vasanth
In board exams, they'll try to repeat the same questions so don't need to bother about it. If you can find some question banks provided by your college then in that try to learn all the questions then are care of the small questions because they often give the questions in confusing way.. If you're confident enough in long answer questions, then go with smaller ones.
All the best.