Hello Lava_Chicken,
If you have created the server but have forgotten the name, do /join own then right-click the book to find the name. To make it super-flat, install multiverse core using /control then restart the server. Once restarted, do the command: /mv create Superflat NORMAL -t flat Once you are there, do /setspawn to make it your server spawn.
- WhenUHackUNoob
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