Help with world loading

I’m trying to put a world that I used in vanilla, for the spoonge, but this world is not being loaded even if it’s in the folder ‘’ world ‘’

Not being loaded? How so? The server must load a world, what world is it loading?

it load only the main world would like it to load a second world for me to leave as survival

Secondary worlds are stored as sub-folders inside the main world folder, the same way Forge manages it. You will probably also need a world management plugin to properly import and use the new world.