How to Delete a World on a Minecraft Java Server

Attention

If you delete the world, it cannot be restored. Create a backup beforehand in case you need the world again later.

Stop the server
Stop your Minecraft Java Edition server.
Connect via SFTP
Connect to your server via SFTP.
Delete the world
Locate the world folder in the main folder and delete it.
Restart the server
Restart your server. A new world will then be generated automatically.