How to use PLC to change the voltage of 380 volts

You understand wrongly. The PLC is programmed with a voltage of 220 or 380. If it can be changed, the PLC can become a power supply.

The S7-200 you are talking about is a relay type. Its output contacts can be connected to 220V voltage, but it is not clear about 380V. You can look at the samples and they will write the contact capacity. , and the required voltage.

This 220V voltage is provided by other external power supplies. If the contacts allow 380V, you can just find a 380V power supply.