If you are talking about NEET, 98% of the questions are from NCERT Books. So lets say if you study everything from NCERT and you can remember all the concepts and can convert them to marks. you can easily score 550 and above. If you planning to prepare for NEET, you can check our Knock out packages at: https://learn.careers360.com/knockout-neet-may/ and as well our article on how to prepare for NEET at home: https://medicine.careers360.com/articles/how-prepare-for-neet-at-home?