How do I play on servers and with friends on Minecraft?

Oh that kinda sucks. Thanks though

Minecraft follows the rules of the platform it's on. On Xbox One, an active Xbox Live Gold subscription
is required for online multiplayer. ... Minecraft on desktop and mobile platforms only requires a free Xbox
Live Account because those platforms do not have a paid online service.

Is the account an adult account or child account?

Do you have Xbox Live Gold?

Check the following settings:

[*]Go to the Xbox One privacy settings.
[*]Set Join multiplayer games to Allow.
[*]You can also change other settings before clicking the Save button.
[*]Play the game again.

"You cannot play online multiplayer because of how your Microsoft account is set up. Review and change your privacy settings at aka.ms/accountsettings."

This was breaking me. But with hours of searching and trying different things this was the key:

To join a Realm in the first place, the xbox setting You can create and join Clubs must be set to Allow.

So even though I had allowed my child to join multiplayer games, they still could not join my Realm.

You can adjust Join Clubs on the Xbox One console or in a browser.

Xbox One Console:

Login as the parent/adult in the family

Account > Family Settings

Choose child's profile

Privacy & online safety

Xbox Live privacy

View details & customise

Friends & clubs

You can create and join clubs: ALLOW

Communication & multiplayer

You can join multiplayer games: Allow

You can play with people outside of Xbox Live: Allow

In a Browser:

https://account.xbox.com/Profile & sign in

Privacy Settings

Choose the Child Account you wish to amend

Choose Xbox One/Windows 10 Online Safety

Adjust the following:

You can play with people outside of Xbox Live: Allow (not sure if this is needed, but as Minecraft is cross-platform I adjusted this)

You can create and join clubs: ALLOW

You can join multiplayer games: Allow

I am having the same issue trying to join a realm on Pocket Edition. Yes, I have a free Xbox Live Account, and yes I have changed all my settings to allow, and yes I have an adult account, not a child account, but I still get the same message everytime,
"You cannot play online multiplayer because of how your microsoft account is set up. "