BCA

Yes, you can take admission for a regular course after distance BCA but some colleges want regular mode for graduation. You need to shortlist colleges for post graduation first and then look into the eligibility criteria.

Yes, you can join the 3 years LLB (Hons) course at Dr. Ambedakar Government Law College, Chennai. The eligibility criteria is as under.
Educational qualifications :- The candidates should have passed any degree (B.A./B.Sc./B.Com./B.B.A./ B.E./B.Tech./M.B.B.S. /B.Pharm/ other graduates in general) and should have secured not less than 60% of the total marks in the aggregate.
The candidates belonging to Scheduled Caste/Scheduled Tribe communities should have secured not less than 55% of the total marks in the aggregate of all subjects.
Age :- No age limit.

Dear Ankur,
Having a post graduate degree will always opens new avenues and better opportunities in career path. Further, nowadays opportunities in Computer Science are flourishing year by year. So, I strongly advise you to pursue your MCA as a lateral entry student after completion of BCA.

Yes, you can get admission in BCA even though you have studied PCB in class 12. BCA admission doesn't considers whether you have studied computer or not,any one interested in BCA course can join after class 12.

BCA Eligibility-
Bachelor of Computer Science requires a candidate to have passed HSC (10+2) exam from any stream with English as passing subject with minimum 45% marks at 12th standard. * Few colleges also demand mathematics as compulsory subject in class 12th.

Yes, you are completely eligible for it. But some universities have different rules so you will have to check from Admission office of your university.

Go through the list of top colleges and study their admission requirements :
https://www.shiksha.com/it-software/ranking/top-bca-colleges-in-Delhi-ncr/96-2-0-10223-0.

You can refer https://www.shiksha.com/it-software/colleges/bca-colleges-lucknow.

Yes, you are eligible to apply.