How to create an infinite size for a multiplayer world?

So I’m currently working on a MMO project, with a very large size (around ~3,000km^2). With the base world size being 20km, how would I make my world large enough so that I can have this large map run?

It seems world origin shifting doesn’t allow for this on a multiplayer project, nor does a dedicated server, or at least that’s what I’m gathering from documentation.