B.Tech Computer Science and Engineering

Well, both have a great scope. B.Tech CSE is something what you may do so there are lot of opportunities. For Mass communication, you should work a little and explore, though it's a very good and updating field.

Amity University is a good university. Faculty was good and you will come out with a good placement package if you really work hard.

No, with that rank you will not get seat in NITs, but with that rank you may get seat in other private universities which considers JEE rank.
All the best.

Check the EAMCET cut-off of this year given below :-
CBIT, Hyderabad
BITS, Hyderabad

Generally, IT section is sub-division of CSE. In CSE, theory and its application both are its considerations but in IT only the application part is there. CSE gives you an opportunity to learn various computer related topics and on the other hand IT focuses on to discover new innovative uses of those fundamental concepts.

You have a chance to get admission in NITS like NIT-Jaipur, Nagpur, Surat, Warangal, Durgapur, etc. for CSE.
Best of luck.