A flat provides you with your own private apartment, whereas a PG is shared accommodation with your roommates.
In a flat, you will have the entire living space to yourself. Flats come with one or more bedrooms, a living room, a kitchen, and a bathroom. Renting a flat is much like owning a house. You have to manage everything yourself, from cooking and laundry to paying your utility bills.
However, in a PG, you share your apartment or a room with others. You will have your own private bedroom. But the living area, kitchen, and bathroom are shared. You may also share your bedroom with a roommate.
You don’t have to take on many responsibilities in a PG. The PG owner will give you food and do your laundry. They will also take care of your utility bills. You only have to pay them a fixed monthly charge.