Hi Kapil,
Yes, you can do MBA in any field. It is not mandatory to have a commerce background for doing MBA. Every year there are lot of B.Tech students who persue MBA. Regarding specialisation, since you are a fresher then you can chose any specialisation of your choice. Many Elite colleges like IIM's offer degree in General Managemnt only. You have an option to select te subjects based on your interest in second year.
Since you are a fresher, marketing would be best option for you. But you can chose from any specialisation like operations, Finance, IT,HR based on your interest.
I would sugget you to focus on preparing for CAT as specialisation is a secondary point to consider.
All the Best
You can do an MBA from any field you want. The eligibility criteria for MBA is only having a bachelor degree with 50% overall. There are many branches of MBA, and all are having good scopes in terms of career and job prospects, so choose according to your interest. You can also do research after doing an MBA if that interests you more rather than a job. Take your time, search through all the resources available in the internet, see what is taught in each field and then match it with your interests. Then you will be able to figure out which field you should choose.
Hope it helps!
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