First of all congratulations, you scored a good rank and based on this rank you can get any iiit you want and also you can enroll in any stream(cse,ece,or any other) but see, I would personally suggest you to go for IIIT ALLAHABAD or IIIT HYDERABAD, these two are the best IIIT's in India. So you can take admission in any of the two and once again congratulations for your performance.