In Google Chrome I open the link to buy the game Minecraft (Mojang) for a Windows computer minecraft.net/ru-ru/store/minecraft-deluxe-collection-pc ...

I am trying to buy using my Belarusian card
Payment error appears...
Then it says that you need to use a bank card from another country.

My child is playing a game, so the money should be put in the child's profile.
I put money from Belarus on my child's Microsoft account ...

I open my phone with VPN.
Very important! VPN is NEED. Activation of the gift card is done on the website Microsoft. Microsoft will check your current IP address. Therefore, I must have the IP address Germany. I run VPN on my phone.

 
On phone I open the site: minecraft.net/ru-ru/store/minecraft-deluxe-collection-pc ...
I log in to my account
Click buy Delux for $39.9

 
Since the child's Microsoft account has the country Germany, so Minecraft will cost 39.9 euros
At steps 1 and 2, I paid in the child's Microsoft account 41.07 euros
I click on the Buy button and buy Minecraft

 
I press DOWNLOAD FOR WINDOWS and the file MinecraftInstaller.exe will be downloaded.

 
Using USB wire:
Copy the file MinecraftInstaller.exe from the phone to the computer.

I run the file MinecraftInstaller.exe on the computer.

Select the version for installation: Minecraft Bedrock Edition

 
I press the button: Install

 
Disk selected for installation C:
And I press the button INSTALL

 
I'm waiting, download 1.68 GB

 
After installation, the game will start by itself:

 
The game started. Log in to your account:

 
I choose a character: