Will I lose my world if I un-enroll from the Minecraft Beta? (XBOX ONE)

I also have both versions of Minecraft and got the newest version for free due to having the Minecraft Xbox One Edition.

If you un-enrol from the beta version you will have to reinstall Minecraft to get the version that isn't part of the beta programme. You won't be charged for the game, the only change will be that you won't be able to go on the worlds that you previously
created or saved on the beta version since it will have the beta features.

If you ever decide that you would like to play the beta version again, you can join the beta programme on the Xbox Insiders Hub then reinstall the game again to have the beta version.

Hope this helps and happy mining

I believe you may be enrolled in Minecraft Beta in the Xbox Insider for PC and you need to un-enroll. Do not rejoin the Beta if you do not want the Beta.

Minecraft Beta Guide and FAQs - Xbox Wire

How to Leave the Beta

NOTE: Before leaving the Minecraft Beta and uninstalling Minecraft, we recommend you back up your Minecraft worlds.

1. On Xbox One or a Windows 10 PC, sign in with the account that registered for the Minecraft Beta and launch the Xbox Insider Hub.
   
2. Navigate to Insider content > Minecraft (or Minecraft for Windows 10 on PC)
   
3. Select Manage.
   
4. Use the radio button to select Unenroll (Leave this preview), then select Done.
   
5. Wait an additional 30-60 minutes after unenrollment completes (Pending no longer appears in the Xbox Insider Hub).
   
6. Uninstall and reinstall Minecraft.
   

I recommend you check your order history on account.microsoft.com to make sure that you have Minecraft purchased on your account.

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.

I am guessing your friend is enrolled into the beta for Minecraft through the xbox insider program

Actually, they sent the beta out to non beta users, and as noted above if they tried to load in their old world, it may be (temporarily) lost. As of 30 minutes ago (via the xbox feed) they advised those who got the beta to uninstall it and reinstall Minecraft
on their xbox.

I already bought minecraft but whenever i try to login it sais its a beta

Please follow these steps...

And if you're already "Enrolled" in the Beta Program for Minecraft, then please ignore steps 1-3.

--1. make sure you are still Enrolled in the Beta through the Xbox Insider Hub.

--2. Make sure Minecraft is installed.

--3. Once you are Enrolled in the Beta and have Minecraft installed, please follow the next steps.

--4. Unenroll from the Beta through the Xbox Insider Hub.

--5. Once you have Unenrolled from the Beta, now uninstall Minecraft from your Xbox One console.

--6. After you Uninstalled Minecraft, hold down the "Power Button" on your console until it completely powers off.

--7. Wait 30 seconds after it's powered off, to power the console back on.

--8. Now power on your Xbox One console, and then Reinstall Minecraft again through the Microsoft Store if you don't see it in your "Ready To Install" section.

--9. You will no longer have, your console registered in the Beta Program for Minecraft... Enjoy! 😎