My dad was telling me there is an old PS1 game called “Valerian” but I can’t find it anywhere. Does anyone know anything? ?

Your dad doesn’t know doodoo. Sounds like he has false memories

According to this page that I found:

Valerian is a cancelled Playstation game that was in development in 1998 by Virtual Studio, a french team owned (?) by Infogrames. There are not many info on the project but thanks to Daydi we found out that the game was based on a french comic, “Valérian and Laureline”. The character model that can be seen in one of the images, it’s identical to the comic’s male protagonist.