Multiple worlds on a minecraft server?

I'm not asking about multiverse, but maybe where I can switch between which one runs on the server so I don't have to make a whole new server for each different world. Not really sure if it's possible but thanks anyways

Its not. Multiserve. Serious.

All you have to do is put each world folder with a unique name in the server directory. Then you can run the server with whichever of those worlds you want to by setting level-name=myworld or whatever the folder name is for that world in server.properties. It does not matter if there are spaces in the folder name, but the name or first word should probably immediately follow the =

If you want to run a different world, simply edit level-name= in server.properties and restart the server.