minecraft singleplayer world in server

[OrangeTurtle]

i have a singleplayer mc world, is there a way to transfer it to a multiplayer world? i saw different folders for the end and nether in the server, and DIM1 and DIM-1 were different folders not in the world folder on the server.

[OneTwoThreee]

Go in to your Minecraft folder (%appdata%\.minecraft), then open the saves folder.
In there, all your Singleplayer worlds are saved.

Now select the Singleplayer world that you want to use for your Multiplayer Server, and drag it into your Minecraft Server folder.

Now, you will already have a folder inside of your Server folder called world. You'll have to delete it.
After you have deleted the world folder, you can rename the Singleplayer world folder (that you dragged into the Server folder) to "world".

Restart your server, and you're done.

Not mine, stolen from:  https://gaming.stackexchange.com/a/296881

With the DuckDuckGo search: singleplayer world to multiplayer world minecraft

 

I think I've seen the world setup you're talking about in a spigot server, it's a custom implementation of the minecraft server so the world setup is a bit different.

Found this which could help: https://www.youtube.com/watch?v=rjIrWTl70nA&feature=youtu.be

From this Reddit answer: https://www.reddit.com/r/SpigotMC/comments/fxadin/server_singleplayer_world/

With the DuckDuckGo search: singleplayer world to spigot

 

I'm putting my searches so if you're stuck again you may be able to find the answer yourself