Is the foundation of the door kitchen 2O cm lower than that of the main room?

Not so good. Although the low foundation of the kitchen can prevent water from spreading into the house, the whole room will be uncoordinated. Children will trip if they walk carelessly, even adults will inevitably trip, which is very inconvenient. And from the perspective of geomantic omen, the sinking of the kitchen is lower than that of the main house, which will also affect the fortune, so it is not good.