Kola Jankov: Help, I found an old Prince of Persia: Two Thrones code. I have tried it on Steam and Uplay. Tell me where to activate it?

OverlorD: This is the key to installing the game itself on the PC.
It is not activated online.
If this is your old disk, you should have known it.
P.S. Here is a generation that is sure that all the keys lead to the steam.