Oh oops. I just saw the exam date it’s 2nd June this year. I’ll be out of town that time. I’ll submit my application through JEE advanced channel then.
But I’ll tell you what I did last year. I had prepared for the test but I fell sick so couldn’t take it.
PCM is all from JEE syllabus, as you know. For biology, mainly I referred to previous papers that I could find online. I had some idea of biology from my KVPY prep in grade 11. If you start now, perhaps you could take some time to go through ncert. Maybe once a week. The questions asked in previous years bio didn’t look really tough to me. By that I mean if you read ncert you’d probably be able to attempt 50-60%. Some of the questions are even solvable through your knowledge of class 10 bio.
That being said, focus on PCM more. Out of the 60 questions, you need to do around 40-42 questions correctly to get an IISER of your choice, if your choice is Pune. Others have lower cutoff than Pune. Preparation for NEST is similar. But from the previous papers, NEST looks like a tad more difficult than IISER.