MBA/PGDM

Hello Shahnawaz,
I am assuming that you have pursued B.Com.
So, in such a case, M.Com will be an extension to your basics of accounting.
Whereas, MBA will give you a diversified knowledge, which will not be only related to accounting, but industry as well.
Depending upon your interest, you can choose either of them.

In India, you may expect 25-30K per month at minimum.

It's always a good option to do MBA post maths honours, you should opt for analytics/operations.

You should take up short term online courses, since it will help you gain specific knowledge in domains. Modules like recruitment/hiring/on-boarding; People Analytics.
Modules in psychology will help you in long run, since you will be dealing with people. People are the most important and critical part of any organization.

It will you get you a good position with a good package. It is really good doing an additional course in the same stream.

NIITE Mumbai is the best MBA/ PGDM colleges in state of Maharastha based on ranking by multiple rating agencies. You may refer to following link for list of top MBA/PGDM colleges in state of Maharasthra: https://www.shiksha.com/mba/ranking/top-mba-colleges-in-maharashtra/2-2-114-0-0

If you want to do it through distance education then you may chose from Symbiosis, ICFAI, SMU. However, if you have time by your side then I suggest you opt for regular mode of education and for it give CAT / MAT exams.

Hello,
If you are not interested in finance, go for MBA marketing, HR, SCM, but pursue in top 50 management colleges in India.

Yes you can do PhD in Management after PGDM provided you did your PGDM from an approved university / institution.