well.maybe its too late...but still i am answering this for someone with the same issue at the time of reading

look if you are too much obsessed about cse then go for nit

but brother you haven't explored any of the btech branches till now and you don't know how would they be

you should opt for IITs and compromise with branch.dude anyway you don't know which branch may interest you...and college life has to be a memorable one......go for iits..branches other than cse also get a very very good placement in IITs

best wises

RD Hacker

Hello Vishal

Congratulations, you have got a descent rank in JEE mains and also got good marks in JEE advanced. I hope your rank will be descent in JEE advanced but I suggest you to opt for nit because you will easily get admission in CSE department in some best NITs. You can get admission in IIT too but you can't able to get admission in CSE department.