Because there is no native PC port, players have only a few (unofficial) ways to experience the game on a computer:
The Xbox 360 version is considered inferior to the Xbox One version, featuring a smaller map, fewer cars, and no dynamic weather. Forza Horizon 2 Free Download Pc
Emulation for the Xbox One is still in its infancy and is not yet a stable way to play the game. Why Can't You Buy it Officially? Because there is no native PC port, players
You can use the Xenia emulator to run the Xbox 360 version of Forza Horizon 2 on a PC. featuring a smaller map