Jamia Millia Islamia

Yes, you will be getting benefit during admission because some seats are reserved for Muslim OBC category.

You can get admission in Jamia Millia Islamia by appearing for entrance exam conduct by the university. For more details, visit: jmi.ac.in

No, you have to pursue it as you are doing.
Well, if you want to pursue BBA on a regular mode then you have to appear for the entrance test and restart from the 1st year.

Commerce and business courses are very good in JMI as its faculty is very cooperative and corporate exposure makes these courses wonderful.

Yes, it is a better option as it leads you to some specific course and this course is not offered by many public university so it is valuable.

It is one of the best institutes in India. Its faculty is very good, infrastructure is mindblowing and has a very peaceful environment and as far as placement is concerned, it is not guaranteed by any public university but everyone gets it at the end of it.

It's very difficult because 50% seats are reserved for Muslims and your rank is 41576. At this rank, your name might come in waiting list.
So, I would suggest you if you stay in Delhi, go for DTU, NSIT through JAC counselling
There, you will definitely get admission.

No.
B.Sc mathematics is a regular course and fully approved by UGC.