Pathology

You need to have PCB to pursue undergraduate courses in pathology.

Go ahead, do MBA in TQM or Healthcare Management.

MBBS is a graduation degree. In medical profession and for your stream i.e. pathologist, MBBS should be done and you need to pursue a specialisation course for the same. Moreover, you can also get into path course through lab course which requires no MBBS.

Please mention the name of the state where you wish to take the admission. This will be better for us to short list the colleges.

Dear,
As per your query, you can consider these options:
Nanotechnology
Biotech
Wildlife Science
Environment
Psychology
Microbiology
Food technology
Neuroscience
And for application process, you need to consult with study abroad consultant.
All the best.

Yes you can do it. In order to pursue full time MBA or PGDM program you need:
Graduation in any field with at least 50% aggregate marks to be eligible to apply.
Then, you need to clear the selection process of the B-school, starting with an entrance test accepted by the B-School. For e.g. CAT, MAT, SNAP, CMAT.