Most important is to revise everything in order of priority. There is no need or point of reading anything new. Your concepts will not be strong in new topics and you will get confused with what you already know. Read from where you read in the past.
Memorise every line of NCERT Biology.
Take tests in your coaching. Solve previous year papers or full syllabus mock tests and time yourself.
But most importantly be calm. Never panic. If you get selected it’s wonderful, if you don’t that’s alright too because you gave your best. That fact itself should make you proud of yourself.
Please read my answer on solving MCQs and exam day strategy. It will help you for sure.