Hello STudent

Every  above average institute for JEE mains  and JEE advanced and for Neet will be sufficient for the preparation for admission of Indian Institute of Science education and research courses and National Institute of Science education and research courses.

Gate 10 years back previous question papers of JEE mains and practices thoroughly a NEET for (bio) . Practice only mainly JEE mains question papers and 41 years books from different publishers and last year's IAT papers if available. This will be sufficient for your preparation to take admission in IISER and Niser courses.

Hope this helps.