Accounting & Commerce

No, it doesn't matter what Bachelor course or stream you have graduated with at all. That's why, a lot of B.Tech and other students attempt these exams. However, Your 10th and 12th marks are taken in account with your CAT score.

CAT is the best exam for Management studies in India. There are also exams like CMAT, XAT, SNAP, etc. All fields are good for MBA, it is only a matter of your interest.

Yes. No questions about it. Regular means you have to be present regularly for class. Most colleges have atleast 75% attendance requirement. So, try not to fall below that or else, you will have to face a lot of trouble at the end of semester.

MBA in India is 2 years and is considered a Masters Degree. In foreign nations however, it can range from 1 year to 3 years. You will have to check each college individually. Also, not all courses are considered a degree. You will again have to confirm that for each college.

After becoming a B.Com graduate, you can seek entry level opportunities in any of the following areas:
Sales
Customer service
Telecalling
Operations
Accounts
Clerical jobs in government or private companies
Admin asssitant
Front office
Sales man in retail showrooms or malls.

Yes, go. You can explore a lot of certificate courses in graphic designing. However, only pursue them if you have keen interest in the said area and have an aptitude for creativity.

This would depend on your interest areas and career aspirations. In case you intend to pursue a career in Technical / research / academics area then M.Com is better, However if you want to move into general management the MBA is better. In case you want a career in Law then you can also look at LL.B. You can also do a lot of certificate course and explore careers in travel & tourism, media, animation, e-commerce, logistics, web designing, accounts. Import & export, etc.

If you are an average student, I would advice you not to explore CA as a course. Rather, you can explore a course keeping in mind your interest areas. The chances of professional success are higher in doing what one likes and enjoys.

Both are professional courses with a separate career path. Keeping in mind your interest areas and skill sets you can decide what you intend to pursue. CA is more tough compared to CS. The range of job opportunities are much larger with a CA qualification compared to a CS qualification.