Mtech preference between IIT K,IIT KGP,IIT roorkee or RA/MS at IIT D or IIT B

I am kinda confused ,I have a gate score of 826 and air 249 , at this score I am having confusion on what IIT's I should go for initially I will be going for placements but I also want to explore something in research based on whether I found it interesting going forward so how should I approach the counselling process, I have been estimating my chances for the ra/ms programs for iit d and iit b but I am not very confident about the written test or interview, also for ta admission i am confused on preference between iit k , kgp , roorkee.