This page of our guide to Tony Hawk's Pro Skater 1+2 explains whether the game is available on Steam.
Currently, Tony Hawk's Pro Skater 1+2 isn't available on Steam.
The PC version will only be available on the Epic Games platform. It will be released on September 4, 2020.
Tony Hawk's Pro Skater 1+2 will be available on both PS4 and Xbox One.