B.Com

You can pursue B.Com + LLB + CS.

If you completed your B.Com with 50% or above then go for MBA in finance from reputed B-School after cracking any of the management entrance exam, which is enough market demand simultaneously your aspiration for going through economics will be supplemented.
Best wishes!

You can do an accounting technician course.
A candidate who opts exclusively for Accounting Technician course and register for it requires to undergo a study course of eight months, 35 hours orientation programme and 100 hours ITT before appearing in Accounting Technician Examination (ATE). It is to be noted that Group-I of Intermediate (IPC) course is equivalent to ATC. After passing the Accounting Technician Examination (ATE), he will also be required to complete 12-month of work experience, as per the guidelines of the Council and on the production of a certificate to this effect; he will be issued Accounting Technician Certificate.

Seeing the last year cut-offs, your chances look slim but wait for the cut-offs to come out for this year.

No, both of these are graduation degrees and there are only a few differences between BAF and B.Com. So, you must choose only one.

Hello,
I understand you wish to pursue higher education in Delhi, but your question isn't clear.
Which course do you wish to pursue?
What are the competitive exams you have appeared for?
How are your academic scores?
Kindly, mention those details with other relevant information for better guidance.

After B.com, the best SAP module for you will be SAP FICO or SAP CRM.

Can I know which colleges offer specialization in B.Com in taxation?
Anyways, for career in taxation the only course you can pursue is CA, you can practice taxation, that too direct or indirect. For more information about the course, feel free to ask.