B.Com

Dear,
For Masters in Architecture, you should have B.Arch degree. According to that, you are not eligible.
For Bachelor's degree, you need to check the age bar and other eligibility criteria.
All the best.

No, you need to complete B.Com then only you can opt for Master's degree (M.Com).

IPU is a good option too.

You can check link for NAAC A grade colleges: https://goo.gl/cqg2sK

You have many options open after completing your graduation.
1. You can take up a full-time job
2. You can do an internship.
3. Go for PG/Master's degree in the area of your choice.
4. Work+study (part-time).
5. Go for specialised courses.

Yes, you can do LLB course after B.com. The duration will be of 3 yrs.
The eligibility criteria for LLB course is that one should have B.A/ B.Sc/ B.Com degree with minimum 40% marks in aggregate for general category and 35% in aggregate for SC/ST students. But, you have to pass the entrance exam and personal interview.

Dear Akhil,
I am sure almost in India, if you want to pursue MBA course, you need to score a minimum of 50% marks in graduation. If you belong to the reserved category then 45% needed.
All the best.

Yes, definitely, you get admission in IIMs but first you have to get very good percentile in CAT, so that you become eligible for IIMs and complete the GD/WAT and PI rounds.
Best of luck.

You will be able to get admission is few colleges affiliated to Delhi University for B.Com. You may visit DU to look at cut off list of 2016 to have an idea in which colleges you have probability to get admission. Refer link:
http://www.du.ac.in/index.php?page=cut-off-2016