How to choose the home improvement socket specification

Buying a house is a top priority for many families? The renovation of the new house is believed to be everyone‘s troubles. The choice of decoration materials and the effect of design are all headaches.
I have to install a switch socket at home, how to choose the socket size? How to choose better? There is no experience, the square insert (120mm * 120mm) and the round (diameter 150mm) thickness is 70mm.
Generally, when installing, put the wire or various signal wires into the cassette, and keep at least 200mm. The upper plane of the cassette should be 20-45MM lower than the final laying surface of the floor. The 1.5-square wire of the socket size is generally used for lamps and switch wires, in the circuit. Ground lines are also commonly used, and there are more two-color lines to distinguish colors. The 2.5 square copper core wire is generally used for the socket line and part of the branch line, and the 4 square copper core line is used for the special line of the circuit main line and the air conditioner and the electric water heater. The above information is to introduce the choice of home improvement socket specifications! I have to install a switch socket at home, how to choose the socket size? How to choose better? There is no experience, the square insert (120mm * 120mm) and the round (diameter 150mm) thickness is 70mm.
Generally, when installing, put the wire or various signal wires into the cassette, and keep at least 200mm. The upper plane of the cassette should be 20-45MM lower than the final laying surface of the floor. The 1.5-square wire of the socket size is generally used for the lamp.