Part Time

Fleximode MBA means a correspondence or a part-time MBA. So, whichever university you are applying which offers a fleximode then check their registration under University Grants Commission (UGC).
Also, as a piece of advise please do a full time MBA if you have the time as that will give you proper insights into the management degree and recruiters prefer them over part-time MBA.

You can do a part-time job while doing BCA degree. BCA degree has a big syllabus and to become a good software engineer, you require to put a lot of effort. Therefore, you must evaluate whether you can handle both studies and job pressure simultaneously.

The eligibility criteria for part-time MBA is a graduation degree in any subject with greater than 50% marks. In addition different universities have min experience requirement varying from 1 to 5 years.

You should pursue your MD full time as you will be gaining exposure and in hand clinical practice. UK can be an option with affordable fees structure of around 50 Lac and no entrance is required. UK degrees are valid in India to practice, visit MCI link: https://goo.gl/5SK1ml
For more details about the program: https://goo.gl/GmQEj2

There are not many Institutes in India which provide MBA in real estate. There would be around 7-8 which provide specialisation in this particular field.
You could look at:
ISTAR, Ahmedabad provides Master of Valuation (Real Estate) but that's a2 year full-time course.
Another option in Guru Gobind Singh Indraprastha University which is in Delhi (Dwarka) has weekend classes in MBA real estate
RNB Global Rajasthan offers MBA (Real Estate and Urban Infrastructure ) but it is a full-time MBA for 2-years.

Air hostess jobs are full time and time-consuming. You cannot do it as part-time along with doing medical studies. For part-time, try to take up ground duty jobs in airport with any airlines as they have shifts.
But, I think a part-time job in airports will be very tiring as you also need to give time to your studies.
If you want to do it for pocket money then take up tutions (self-employed), rather that working.