Business Management Studies

See, there is no problem, if you are from Science field, you can also do BBA. And check this link for details regarding BBA:https://www.shiksha.com/bba-bachelor-of-business-administration-chp

You can apply for B.Sc. Computer Science at VIT and the chances that you get selected through counselling is high with 75+%. You can either pursue MCA or M.Sc Computer Science after the graduation of your Bachelor's degree.

Refer to this link to compare the colleges as per their rating:
https://www.shiksha.com/bba/colleges/bba-colleges-Gujarat

Both are different in their respective fields and based on your future goals, you have to decide what you should be doing. A PGDM in Canada from some reputed university might fetch you good chances on an international placement, but two year MBA course in India, considering you are talking about the IIMs or top notch Private Institutes like SIBM or MDI, would earn you more respect in India during placements and Career beyond. So the decision is based on your career goals. Good luck.

Presidency Bangalore is a better option since it is a old and renowned college and has good faculty members.

Yes, you can do MBA provided the university you pursued B.Com from is accredited by UGC and you have 50% score.

https://www.shiksha.com/mba/colleges/mba-colleges-Hyderabad
Kindly check the link you can the detail information regarding fees structure and everything. If you have any doubts you can ask.

Yes, there is scope of getting into a government college.

Yes, Delhi Technological University is a very good option for pursuing BBA or any other course, It is a very good option for bachelor's degree. Further information about Delhi Technology University is available here:
https://www.shiksha.com/university/dtu-delhi-technological-university-dce-23920