First and foremost – you have to take permission from the Society. When you take Flower Bed space inside your home, you end up changing Elevation (look) of the building. Once the society gives you permission then you have to see whether the place can be enclosed, how much load it will take and if brick work can be done. Only after all these consideration, you can decide what kind of new construction can be done.
Officially, you have to consult a RCC designer before you do the work. The RCC designer tells you if the beam or column is capable of taking the load where you are constructing. This is important because if not done correctly, it can damage some part of building. Also by law, in certain cases you have to take permission from BMC for the work you are doing. Sometimes you may have to pay some formal fees to the BMC for the work.
If you are living in a society, where already, other neighbors has added flower Bed inside, then things are very straight forward for you. Because your neighbors have already done all discovery work.