They seem to have only one "node" so far, because the software is still in alpha? That's what their docs seem to say[1].
All your data primarily syncs to the encrypted backup node in the current alpha. For alpha testers, the application is always connected to the backup node and cannot be disconnected.
Their homepage could tell this more clearly. It doesn't look like it's in alpha.[1] https://doc.anytype.io/d/troubleshooting/self-host-your-back...