If you are interest in doing a BBA there are many decent colleges such as SP Jain, NMIMS, etc based out of Mumbai...To do an MBA you need an graduation of some kind for all the top colleges.

If you want to enter into any good b schools, you have to clear competitive exams like CAT, XAT. These exams test your quantitative and verbal abilities, data interpretation and logical reasoning and a few tests include general awareness also. For long term you have to increase your reading speed, vocabulary and strengthen mathematical ability. Even though tests claim that they will ask 8,9, and 10th class syllabus, the standard of questions are set in a way that even engineers can not easily score in maths. Another important aspect is that you have to focus on graduation scores and it carry a lot of weight in admission process of top bschools. Another piece of advice is that 95% of MBA graduates don't have BBA. BBA and MBA sounds similar like BTech and MTech, but there is no significant competitive advantage for BBA graduate in MBA.

If you have a clear idea of which field you wish to move into after class xii, try doing a bit of research in that field in terms of:
- Course content
- Exposure to real life problem
- Inclination with your interests
- And to some extent, job/career opportunities

BBA/MBA surely seems a good option. I can help you with more inputs if you can be a bit more clear of your aspirations and educational background.

BBA krlo uske bad MBA karlena