Hi Renu,
I would advice you to go with your interest .. If u are interested in petroleum engineering and reasearch thn go for IISER and RGIPT.. go for the branch you like ....u need to simply have passion for what u are doing. so just clear ur mind and think of what u love best. dont compromise on that coz u got to live with it all ur life !
IIT is a brand name .. obviosly it wud be advantageous.. but IISER and RGIPT are reputed ones .. so go with interest.
Please feel free to post as many doubts on our disucssion forum as you can. If you find any question difficult to understand - post it here and we will get you the answer and detailed solution very quickly. We are all IITians and here to help you in your IIT JEE preparation.
All the best.
Regards
Vijay Luxmi