Here are some preparation tips for JEE Main Physics.
Don’t solve the previous year's questions, before finishing the syllabus. It will only be a waste of time.
If you are only preparing for JEE Main then reading NCERT books will be enough to score above 200+. Read every chapter from NCERT, all the chapters are equally important. However, if you want to score well in JEE Advanced too, you should have a clear understanding of each and every concept. Once your fundamentals are clear, you can start practicing problems. DC Pandey and HC Verma are great for clearing concepts and numerical practice.