Ok hello, so a while ago I joined the Microsoft beta program for minecraft to play with a...

I had a similar issue a while ago it sounds like you might be in the beta program. It should say on the beta somewhere on the title screen you can opt out using these steps.

https://feedback.minecraft.net/hc/en-us/articles/360004438671-How-to-Join-and-leave-the-Minecraft-Beta

Your son is playing on the official release channel for Minecraft. His 1.12 version is currently the latest official version, whereas his friends have joined the Insider Program and are playing a beta test version of Minecraft.

His friends can either un-enroll from the Beta Insider Program, or you son can try to join the Insider Program and update his Minecraft to a beta version.

Be aware however, that beta version still contain untested parts, and the game can crash, malfunction and in turn destroy worlds if an error occurs.

If your son is still willing to test the Beta, he can download the free Insider app from the store, and join the Minecraft Beta.

Then he'll have to download/update his Minecraft to the newer beta version.

Hello, i was wondering if you are part of the Insider Program on The Xbox One ? If you are you might want to check and see if you joined the Minecraft beta. I only say this because i’m in the insider program and my Minecraft would never load either until
a friend of mine asked if i was in the insider program beta and i said yes. Then he told me to leave the Minecraft beta program within the insider program and since then i’ve had no issues at all with minecraft. To check you go to the insider program app on
your Xbox One and then to to insider content and then click on Minecraft then leave the Minecraft beta. I hope this helps you out because i spent forever trying to figure out this problem.

Is it possible that you have joined the Minecraft Insider Beta program, and you have a newer Minecraft Beta version than your friends?

You need to wait up to 72 hours after joining Minecraft Beta for you to be enlisted on the program and get the update through the Microsoft Store.