how to score atleast 100 in neet physics?

In order to score 100 you  need to solve 25 questions correctly.  So pay more attention to topics covering more questions in exam. Modern physics,  semiconductors ,optics, electrostats, magnetism, thermodynamics and some chapters of mechanics as per your convenience or interest.  That much will probably serve almost 25 questions.  All you need is to revise them atleast 3  times with previous year asked questions.