Hello,

Well first solve last 3 years kvpy question paper provided on the official website. Other  most important thing to do is revision. If you don't have any KVPY specific book, revise physics from HCV(Don't forget to do objective questions from this book), chemistry from NCERT and maths from any good book written for IIT.

For more information visit the below link:

https://school.careers360.com/articles/how-to-prepare-for-kvpy

All the best!!!