Anil with 81 marks in JEE Advance examination it is very difficult for you to clear the cut-off until and unless the cut-off drops down to a huge extent in comparison to last year which was 115 marks for OBC category. It is expected to fall down but to such a great extent has very less probability. So, getting in any IIT has almost zero percent chance. 

Now for your JEE Mains please mention your OBC category rank in the comment so we can figure out your chance of getting into any NIT and IIIT. Without OBC category rank we cannot predict now what are your chances of getting admission in any of the government colleges.

Feel free to ask if you have any more queries. All the best!!