This guide is just one person’s experience with one version of Minecraft. There is a lot that could be different or change over time. You are a smart person, so I trust that you can figure it out.
1. Create a Microsoft child account
*Note: This is only if you want to create an account for your child. Another option would be to let them use your account.
You can create a child account by logging into your Microsoft account (https://login.live.com/) and selecting the “Family” item in the top navigation.
Once there, you would click one of the + icon to add the account.
2. Adjust the privacy settings for the child account in the Xbox settings (Because having it all in the Microsoft account settings would be too easy)
Go to the Xbox settings (https://account.xbox.com/) and get the gamertag you want and do whatever else you feel compelled to do.
3. Open up Minecraft
Choose the “Play” option.
4. If you want to invite someone to play in your world, choose the world.
5. Start the world
At the top of the screen in the middle, there is a pause button. Tapping that will pause the game and bring up an options screen.
6. Invite a friend to the game
On the right side of the screen you’ll see a button that will allow you to invite a friend
When you tap that button you’ll be able to find the friend through Facebook, phone contacts, or by gamertag. I think Gamertag is the easiest.
Once you invite a friend they will be able to play the game with you.
7. If someone invites you to a game
You will see when the friend is online and you are able to join the world in the “Friends” tab on the screen screen after choosing “Play” on the initial screen when you open up Minecraft