Minecraft disappeared from Microsoft account after reinstalling Windows

Yes, it is possible to install Minecraft Bedrock Edition on PC, in the Launcher it appears with the name "Minecraft for Windows".

Regarding the migration question, don't worry, your Minecraft Java Edition will not disappear, the only thing that will change is that the game license will be linked to the Microsoft account where you migrate it and after that to be able to run the game you will only have to log in with your Microsoft account instead of your Mojang account.

Sign in the Microsoft Store with the old account. Then, install "Minecraft for Windows 10", it should be free. After that, sign out your old account from the Microsoft Store. Open up "Minecraft for Windows 10", then sign in with your new account. You will
get updates for free if you do the following. I hope this helps.

When you redeemed your Java Minecraft on Mojang, you have gotten a 5x5 code to redeem Minecraft on the Windows 10 store.

This redemption is a separate service of your Mojang account, and it's possible to use a Microsoft Account email that is different from your Mojang account email.

Mojang (which gives you Java Minecraft) is separate from the Microsoft Windows Store App, which uses a Microsoft Account email when you redeemed that 5x5 code.

After redemption of that code, the Windows 10 Minecraft is tied to the Microsoft Account email you used on your Windows 10 PC. From then on, you don't really need the Mojang account anymore, if you only want to play on Windows 10. You will then get the game
from the Windows 10 store only, with the E-Mail account you used on the Windows 10 store during code redemption.

So make sure you are signed in with the Microsoft Account email (which might not necessarily be the Mojang account email) when you use the Windows 10 Store app to re-download your Windows 10 Minecraft again.

Hello Karezlatef, welcome to the Microsoft community, I'll be happy to help you today;

I understand that you want to exit the beta version of Minecraft;

On a Windows 10 PC, sign in with your Minecraft Beta account and launch the Xbox Insider Hub (If you don't have the app, download it from the Microsoft Store);

Navigate to Insider Content > Minecraft (or Minecraft for Windows 10 on PC)

Select Manage;

Use the radio button to select Unsubscribe (leave this view) and then select Done.

Please wait another 30-60 minutes after unsubscribing is complete (Pending no longer appears in the Xbox Insider Hub).

Uninstall and reinstall Minecraft;

Hope this helps, see you soon!

When you Uninstall the Game you maked Backup of you Worlds? Try restore the Backup if you have