NIMCET

The cut-off for General is 662, SC- 4263 and OBC- 1711.

Can you please tell me which entrance exam do you wish to appear for, so that I can guide you better?

Yes, you are eligible for NIMCET, because you have a graduation degree along one subject, as a computer Science.

The eligibility should be graduate with degree (BCA/B.Sc (Hons.)/B.Sc/BIT) as per 10+2+3 pattern from a recognised university to apply for NIMCET. Since you are doing B.Com., you are not eligible for the same.
Good luck.

Yes, you can get but you have to crack the JEE Mains entrance exam.

NIT colleges are the best colleges for MCA. NIT colleges ranking for MCA (you should fill in this order) NIT Tiruchirappalli (Trichy) NIT Tiruchirappalli (Trichy) The top most college for MCA in India. NIT Surathkal. NIT Warangal. MNNIT Allahabad. NIT Calicut. MANIT Bhopal. NIT Durgapur. Top MCA Colleges/Institutes: ITM University, Gwalior. Jamia Millia Islamia, New Delhi. IIT Roorkee. NIT, Surathkal. Birla Institute of Technology (BITS), Ranchi. NIT, Rourkela. PSG College of Technology, Coimbatore. Vellore Institute Of Technology, Vellore.

I think, yes you can get HBTU for MCA. NIMCET have around 800-900 seats for NITs. And after 900 ranks, students go to other prestigious colleges. HBTU is one of them. In HBTU, 60 seats for MCA are available. For more details, see official site.