Can't play multiplayer in Minecraft

I'm on Windows 10 trying to play Minecraft Java Edition, but the "Multiplayer" button is greyed out for me with the message "Multiplayer is disabled. Please check your Microsoft account settings". I downloaded the game from from minecraft.net this morning.





I have already adjusted the Privacy & Online Safety settings in Xbox live (https://account.xbox.com/en-us/settings).













I have also tried to change the Microsoft Family App settings (https://account.microsoft.com/family/home), but clicking on the tiles like "Content filters" on the homescreen just opens support articles. Clicking on myself does nothing. I'm not sure how to edit permissions on this page.

Additionally, I have also checked Xbox Networking in the Windows settings, and I have connectivity.





I have logged in/out of my Microsoft account in the Minecraft Launcher, and restarted my modem, router and computer. I still have the issue. What else can I do?

:)