BBA

a there is no sponsorship in BBA for any category

Primarily you should try on government colleges than after try for private colleges for your career. You should go in metros or big cities for better exposure.

You should go for it.
Good luck.

Yes of course
There is no any criteria that you have to study Maths in order to do BBA

Ranjan, 66% in commerce stream in CBSE thats really good and according to my view B.com is better choice because it's scope is much greater than BBA. After B.com you have lot more options to choose from for higher studies. you can go for M.com, MBA , and many more PG courses. You have to study hard to complete B.Com coz without a good percent it will be lill bit difficult for next step .
And Ranjan you are talking about competitive exams right, so during Graduation you also get time to be prepare for competitive exam but you have to study hard.
Best of Luck.!!!!

You can try for BBA.

Hi
Check for BBA colleges here:
https://www.shiksha.com/bba/colleges/bba-bms-bbm-bbs-colleges-in-patna
You may look for MBA in the same manner here.

Dear Vaibhav,
Best college for BBA with good exposure and placements is "Shaheed Sukhdev College of Delhi University". It's a very good and reputed college for BBA under Delhi University. For entrance exam details you can check DU's official web site.
Good luck.