B.Com

Distance course is best when it is pursued from IGNOU. Dont go for any other distance course.

in my opinion, do not go for a PGD. Diploma does not hold that muh value as compared to a degree.

I am not really sure about the market outlook but as far as career is concerned I can share a few things that I know.
For making a career into SAP FI you require at least 2 years of domain experience so that your placement happens smoothly after the certification exam.
Your career starts as a SAP FI fresher and then you go on to become a Consultant within 6 months to 2 years, depending on your performance. You are then put on core teams and allocated clients, for which travelling and relocation becomes a must in this kind of a job

You can choose it from here:
https://www.shiksha.com/accounting-commerce/colleges/b-com-colleges-kolkata?ct[]=130&bc[]=6&rf=filters&co[]=Public&uaf[]=college_ownership

For MBA, english is required. MBA entrance will contain english questions. Dont go for MBA. Do some other course like MCom.

Make a list of colleges according to your location preference and check the eligibility criteria in each of them. Then apply for it.

You must go for psychology as primarily HR has evolved from sociology and psychology. Hence people with a bachelors in such fields have an edge over other students pursuing HR as their PG course.

Yes, you will have to clear CAT or MAT or XAT or others. See: https://www.shiksha.com/International-Institute-Of-Business-Studies-Iibs-Kolkata-courses-offered-details-institute-college-listingcoursetab-30315

B.Com will lead you to M.Com, MBA, CA, Laws, CFA, etc. and BCA will lead you to MCA, MBA, MIM, etc.
Decide well!