Colleges in Hyderabad

Hello Dear,
Yes, you are eligible for it.

Yes, you are eligible but I am not sure why you want to shift from masters in technology degree to a masters in science because it is out of the regular curriculum but anyway best of luck.

For Indian citizens, you can directly apply to the course on their website, provided your Diploma is equivalent to 12th.

NIFT is a premier academic institute of design, management and technology, with aims at establishing benchmarks for quality of professionals that go into the fashion industry. The Institute provides comprehensive and state of the art infrastructure and equipment to impart both practical and theoretical training.
So in my opinion if you are not satisfied there than immediately plan to shift from there. The registration process of NIFT will starts in the last week of this month. Hence plan accordingly.

Osmania University is good for MBA. Institutes for OUCET are:
Erudite coaching centre
Spark academyCoaching centre

In order to apply for Diploma and graduate-level tourism courses, you must have completed 10+2 (any stream) from a recognized board of education. Admissions to the diploma are done on the basis of merit in class 12 board exam or on the basis of state-level entrance exams.
So, If you have merit you can blindly go for it, and you will get admission into an excellent college, if you don't have merit then it's possible that you might get admission in descent college, but not an excellent one. However, I suggest that since you are working go for correspondence.