Degree

MBA has a wider scope like-
1) Finance
2) Marketing
3) Human Resource
4) Information Technology
5) Operations
You can choose any one according to your interest.

You need to go to your college and ask this question because they may have various terms and conditions for re examination of student.

No, you cannot do that because universities track you from you attendance and examination you perform which is mandatory to get your degree.

Hi Dinesh, Eligibility:
Candidate must have passed 10+2 or equivalent from a recognized board. Candidates also have the option to opt for fast track course concluding in 3 months.Fees
Viewing info for
General Category
Total Fees
INR 14,900
International student fee could vary depending on INR value of US dollar. Further, please follow official website for more details.

I guess, there are no age limit for most of the Masters. So, upon your interest you can pursue one.

No, it can't be. If you have seen some cases, they might be fraud. So, don't use short cut. All the best.

Having work experience is not required to join MBA. For those who you are working and wish to pursue MBA can go for Executive MBA. For better understanding, please read the article in the link below. https://www.shiksha.com/business-management-studies/articles/your-career-after-doing-an-executive-mba-blogId-4546.