Having an administrator on the Vintage Story server is necessary, and it's even better if there is a whole team of administration/moderators on the server, as it allows for convenient and timely management. For example, changing the game map (time, weather, etc.), adjusting the difficulty, or banning/blocking players who violate server rules or use cheats.
First, open the game panel of your server and navigate to the Console section.
Start the server and go to the command line. Then type the command /op player's nickname and press Enter.
Vintage Story servers support a wide range of game commands, allowing you to manage the server in any way you like. Learn more about using commands on the official game website.