M.Tech

Check out this link: http://admissions.daiict.ac.in/pages/mtech.html#program-overview. It will be helpful.

You will need GATE scores to join in M.Tech ICT. So since you haven't written GATE, you cannot apply. Sorry but all the best for your future.

There are many other options too such as Database management, Big data and data analytics. It depends on your interest basically. And you can always do a job first and then get your post graduation degree.

Experience certificate from the employer is required.
The institute will conduct interview, and written test (if required).
Valid GATE score, if any would be an additional benefit.

As of now, there is no M.Tech in Presidency University, Bangalore. And if you're looking forward doing B.Tech post your plus two with PCB, all the beaches of engineering are opened to choose from apart from CS.

Indian Institute of Science, Bangalore. Indian Institute of Science was founded by Jamshetji Nusserwanji Tata in 1909. The institute was established to promote scientific temper and research attitude in the nation. With 34 departments and centers organized into the 6 divisions, IISC offers the industry a large talent pool to choose from.

No, you need to do your M.Sc. Also, since its is a 12+4 criteria to oursue M.Tech and apart form this you also need to have that level of string technical base which is not possible to build only through B.Sc.