What should I do if it is not possible to purchase the game on Steam and in gog due to the fact that I live in Belarus? Are there any solutions?
There is no way to buy the game
can buy key and activate it in steam
on your own risk you can ask person from other region e.g. Kazahstan to buy you the game as a gift and pay them for it.
Highly not recommended to buy steam accounts with game, you may not be able to use them if previous owner already linked game to FAF