CBSE 12th

Hi Mehma,
First thing you are from a commerce background so you cannot pursue computer Science as a main course. You can study finance, business, accounts, etc. These areas have good scope everywhere. Know your own interests first. Your grades are very good, you should try to apply.
Education loans and scholarships are available. However, see that it's a good university abroad. Take help of some consultancy to guide or help you out. If current situation is difficult you can plan to study your Masters abroad.

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Hi,
Yes, you can take ACT, no reason why you can't. First however check the admission requirements, check if ACT is required or not. It's basically required to study in USA.

To do your MBA you need to do graduation first because graduation is the minimum eligibility criteria for doing MBA.
You can do your graduation in any stream (which you like most).

Hello Ayushi,
It seems that you are in a Shakespearen dilemma. But firstly do not worry. This is normal. Let me first assure you are all the three choices of yours are good. I would strongly advise you to select that course which fascinates you the most. Study hard and success will be yours to test.

No, you cannot get any engineering college.

Hello Chetan,
You may refer the link below for the list of BCA colleges in Ludhiana:
https://www.shiksha.com/it-software/colleges/bca-colleges-Ludhiana

Yes, you can do CA after completing computer science.

You can go for private engineering colleges. Don't waste your precious time by taking drops again and again.