B.Sc

It would depend on the institution. But generally the fee is around INR 2-4 Lacs.

No you cannot do that. You do not have any 1st year basics of B.Sc. Aviation.

Hello,
To be eligible for M.Sc. You must have completed the graduation degree, The IIT JAM exam is conducted for the admission into IITs or IISc or other top institutes for M.Sc. Integrated Ph.D. and integrated courses. The graduation degree is the minimum eligibility for the same while there is no a

Yes, if you had done class 12th, then you are eligible for this course. Best of luck.

Yes, you are eligible. But please double check with individual institution.

Yes, you can. For Masters from any subject, you must have graduation.

Yes, you can do it. There are so many colleges that offer M.Sc after a long gap too.

If want to go in teaching field in future then choose the latter one otherwise B.Ed is of no worth to you.

Yes, there are direct admission facilities for students who are planning to enter this field.

It would depend on where you are planning to study. Some colleges do have such quota. But an NRI can study just like any other indian.