Hi Shakti,
Admsiions to NITs and IITs are done on the basis of JEE marks. First, you will have to answer JEE-Mains. For NITs, JEE-Mains scores are enough. A percentile of 80+ for reserved categories and 95+ for open category is desired. If you do well in JEE-Mains, you will be eligible for JEE-Advanced. Admissions to IITs will only be done according to your JEE-Advanced marks.For IITs, your rank will need to be in the top 3000-or-so.
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