Don’t go for big fat books just follow ncert books.

For biology ncert is the key to score 300 marks in neet, for each chapter read ncert multiple times, then solve mcq from any good book. Do analysis after solving mcq where you are making mistakes and try to make that part strong by revising it from ncert .

For chemistry -

Physical -practice is must for physical chemistry, learn all the formulae of all the chapters very well. Solve mcq from balaji publication books. Atlast solve some last year questions.

Inorganic - Just study ncert book, each question will come from it. Memorise all important process, structure, colour of the compound. Then solve last year questions. Prepare very well p block and chemical bonding.

Organic - GOC is the key to score very high marks in organic. So understand each and every mechanism very well and practice large amount of questions on it. Don't leave polymer, biomolecules they are very easy and question come each year from these chapters.

Physics - Every medical student have fear from this subject. Scoring marks in this subject is not very difficult you just have to prepare well. Physics is all about concept so try to understand each concept very well. First read from ncert then try to solve mcq of low level to gain confidence, after that try solving higher level questions.