PVP is a mode that allows players to fight against each other. Since, in Minecraft, at the death of the player, his entire resources fall from him, the battles acquire a very important role. The murder of a player can save a lot of time to search for rare resources.
It is worth being very careful not to attack a player who has enchanted swords, diamond armor and many different potions in the inventory.
This mode is automatically turned on when creating a server, but if it is disconnected for some reason, you need to change the PVP parameter to True in the Server file.Properties. This file is in the game folder and is responsible for its settings.