Assuming asking for NEET, You should try to clear your concepts and your fundamentals should be strong. You can follow your text books in order to make your base strong and can do practise as much you can. Focus on the topics which carries more weightage in the exam. You can solve MCQs related to them for your practice.

You can check the weightage & important topics in Physics with the given below link.

https://medicine.careers360.com/articles/neet-chapter-wise-weightage-and-important-topics

Good Luck!