BCA

No college in India will be offering admissions at this point of time. You are too late. Now, wait for the next admission season.

Hi Divyansh,
For some colleges, the answer is 'yes'. It depends on the college. You have to check the eligibility before applying. Please refer to this link:
https://www.shiksha.com/it-software/bca-chp14

College change or university change is only possible after first year (not in 4th semester) and that is also dependent on the college and university. Some universities allow it and some won't plus you need to have good scores in first year to apply for the same. For further details, contact the college authorities.

Hi Santosh, BCA is a 3-year degree and I doubt if it will be accepted. You have to first check with the universities, many will ask you to complete the first year of an MS degree in India itself. Overall academics must be very sound, more than 75% is recommended.

You must go for some PG Diploma in mechanical or automobile as you won't be eligible for any full time degree (M.Tech ME) in automobile.

Yes, BCA students can apply for an MBA. Wish you all the best for MBA entrance exams.

Hi,
You may but I would advise not to do in parallel. You won't concentrate either of the degrees and ultimate you will land up with average marks. If you are confident enough then you are eligible to pursue both at same time.

Thank you for reaching us. You may refer to below link.
https://www.shiksha.com/search/?q=MCA&bc[]=103&sa=1^0^0^103^0^0^0^0^0^0^0^0^0^0^bc:103&rf=searchwidget&ct[]=1