I need help loading a custom map onto my server

[Pawlark]

I've made a building into the vanilla map and I tested it on a Solo world to check if it loaded correctly (which it did). I want to have it load into my Private server but I can't get pass the "Loading World" prompt when starting the server. I'm not sure what I'm suppose to do, only thing that comes to mind is to make my map/building into a Workshop mod. I have it selected as a mod  and map before launching the server. It doesn't show in workshop so that's what I assume is the issue to why it won't load. Any help will be appreciated <3