Good afternoon

Look as you have a PwD quota, your chance of getting IIT or NIT is very high. You have to score very less marks as compared to general students. For example, Where the cut-off for general is around 120, there the cutoff for general PwD is around 20. But my suggestion is to forget about your quota at the time of preparation and study hard. If you gave the jee mains and advanced well you will end up getting a very good IIT with your preferable branch.

All the best