I am afraid you are into a dangerous orbit. Doing an MBA( Finance) is very good. But am not able to understand why you are so keen to do a B.Ed degree course after your MBA.
However, since you seem to keen to teach in schools, please do note the following:-
1. After your MBA course, you will be eligible to each only Accountancy and Commerce for the plus two students, as the majority of schools, pan-India, have only one syllabus throughout the first ten years up to the std X and then the specialization starts.
2. Unless you have an M.Com degree and then B.Ed, you are unlikely to be paid a high salary but you can always go through the experience route. Try to apply to all residential schools. The biggest advantage of such schools is that your salary is decent, and you will be given some reasonably good accommodation and also free food, at times. In any case, a good experience of five years will help you to go to the next level.
3. You must immediately register yourself for the IWA course and aim to complete at least the inter-level of that course. This will enable you to gather a lot of insight in cost accounting and you can also use such knowledge in your career as a teacher. And this will also help you to interpret the balance sheet of several companies and so on. You can become an asset to the school. After that, you also need to do the M.Ed course and if possible, also do the M.Com course. Please do note that several Universities in India have a part-time facility to do the M.Ed course.
4. You must be prepared to grow with experience. You will have good competition. At times, the principal himself may have a commerce qualification and also teach. Hence, you need to be really smart to make a mark for yourself.
5. If you are good enough, after the ICWA course ( I mean the total course) you can register for the doctorate program in commerce and go ahead. You can even join a college. However, taking the NET and SLET examinations can help you a big deal.
All the very best.