India

Hi Purav,
Some of the popular MBBS colleges (Maharastra & Gujarat) are:
Armed Forces Medical College, Pune
Grant Medical College, Mumbai
Seth Gs Medical College, Mumbai
Mahatma Gandhi Institute of Medical Sciences, Wardha
Lokmanya Tilak Municipal Medical College, Mumbai
Byramjee Jeejeebhoy Government Medic

Please refer to the link provided below for the details of admission in M.Sc chemistry in Singhania University. You should be able to download the brochure which contains details regarding admissions in various M.Sc courses.
Link: https://www.google.co.in/search?dcr=0&q=Singhania+university+shiksha&o

Wisdom School of Management,Kochi
Insparc Technologies Pvt Ltd., Kochi.
Above are the institutions offering M.Tech in Kerala.

Check the link provided for all the college details for B.Sc in Agriculture:
https://www.shiksha.com/science/colleges/b-sc-agriculture-colleges-maharashtra

IIM-Ahmadabad is the best institute in India for doing MBA/PGDM based on ranking by multiple rating agencies, course content, faculty, infrastructure, previous placement record, alumni network and brand value. You may refer to the ranking of B-Schools in India here:
https://www.shiksha.com/mba/ranki

Here are some colleges you can consider:
1.INDIAN INSTITUTE OF SPACE SCIENCE AND TECHNOLOGY - [IIST], THIRUVANANTHAPURAM
2.NATIONAL INSTITUTE OF TECHNOLOGY - [NITC], CALICUTCALICUT, KERALA
3.GOVERNMENT COLLEGE OF ENGINEERING - [GCE], KANNURKANNUR, KERALA
MAR ATHANASIUS COLLEGE OF ENGINEERING - [MACE],

Yes, you are eligible to pursue graduation again at any age no restriction but your marks need to be up to the level of college.

Yes, you are eligible to pursue pharmacy course. NIOS is a recognised board.