If you complete your graduation from IIM Indore then you are already doing an integrated course in BBA plus MBA which is a 5 year program.
Therefore your MBA will be done.

Then you can straight away start with work experience or further education.

But then incase you want to do one more MBA program from oxford university then you will be required to clear GMAT entrance exam along with English proficiency entrance test.

Rest based on your score in the test you will be further shortlisted.

Hope this helps.
Good luck!