Hi, is it possible to somehow use the PS4 controller in order to play The Witcher 2 om my Mac or Windows 10?
If yes I will be happy for some tutorial on how to it with a third party app or some other way.
Thanks.

I don't know if it works for you yet but you can use DS4Windows. you can look for a tutorial on youtube, what the program does is that it recognizes the control as if it were one from xbox

The controller API from STEAM is the best thing to play with any kind of controller to any games.

You can add non steam games to steam to use steam functionality with your GOG games.

Steam detects ps4 controller without the need for 3rd party program.