IGNOU - Indira Gandhi National Open University

No, there is no age limit.

It's not possible to do M.Com without any Bachelor's degree so after receiving the Bachelor's degree you can take admission for M.Com.

The candidate should be 12th pass to take admission in BTS course in IGNOU.

Please refer to the link provided below for details regarding a Master of Library and Information Science (MLISc.) from Indira Gandhi National Open University. Regards.
https://www.shiksha.com/humanities-social-sciences/library-information-science/course/master-of-library-and-information-science-mlisc-indira-gandhi-national-open-university-saket-delhi-110858

IGNOU is a central university, which means that it is funded by the government and falls under the jurisdication of the MHRD. Regards.

You can apply online with the required details. IGNOU conducts its programs in two sessions July session and the January session. The forms are available in the month of June for January admission cycle.

You can complete your B.Ed while teaching.
Privately, you can apply for the course you want.

Fee of 4,600 INR is for the entire course (BCA from IGNOU). Regards.

The registrations will start after May 2018.

Please refer to the link provided below for details regarding Master of Arts (Sociology) from Indira Gandhi National Open University. You should be able to download college brochure which contains important information regarding eligibility for this particular course and admission process followed. Regards.
https://www.shiksha.com/humanities-social-sciences/sociology/course/master-of-arts-sociology-indira-gandhi-national-open-university-saket-delhi-110849