Who joins your server directly
On Windows, Android and iOS, the game's Servers tab lets you add a server with its IP address and port, shown on the panel's dashboard. All these players play together in the same world.
Consoles
On Xbox, PlayStation and Nintendo Switch, the Servers tab offers no button to add an address: it shows Mojang's partner servers. A console player therefore cannot type your server's address in the game.
The community has built workarounds. BedrockConnect, for example, changes the console's DNS to replace a partner server with a list of servers of your choice; other tools show the server in the Xbox friends list. They come neither from Mojang nor from us, and whether they work depends on the console, the network and game updates: we do not install them and cannot guarantee they work.
Choose who gets in
The panel's Players page manages the allowlist and the operators. With the Microsoft accounts setting (online-mode) on, every player must be signed in to their Microsoft account to join.