Aniket first of all why you are working for 3 different fields at a single time. You need to figure out your interest, what you actually like, in which field you want to make your career. If you really interested in management, you want to enter into the corporate world then drop both the ideas of CS executive and MCom. For doing MBA you need to have a graduation degree with atleast 50%+ as the eligibility criteria for most of the colleges.

The whole process of getting admission into one of the top colleges to pursue your MBA degree is a very long and tough process. Every year competition is growing at a very high rate. The first stage of ending up with a very good score/good percentile in any of the MBA exam is the toughest stage. And to get admission in any MBA college clearing an exam is not enough you need to have excellent academic records (10th, 12th and graduation percentage), work experience is also counted even your graduation degree (engineer/non-engineer), your gender is also given weightage. And these all parameters are used to call you for the second round of GD, WAT and Personal Interview. If you failed to perform in this stage you won't get admission.

I am not telling you all this to scare you but what I mean if you can't do MBA, CS Executive and MCom preparation altogether. It's very necessary to know about your interest and jump into with your full preparation in order to maximize your result. It doesn't need to be MBA only if you like MCom then go for it and scrap off MBA from your mind. But make sure you make a wise decision asap.

All the best for your preparations!!