Hi Fripi_318,
I am Dave, I will help you with this.
'This PC' is not actually a location on your PC, it is just a virtual location in File Explorer.
Typically all your files would be stored in your user folder in C:Users in the library folders like Documents, Desktop, Downloads, pictures...etc.
Also, in Windows the default location for the Documents, Desktop and Pictures folders is inside the OneDrive folder in your use folder in C:Users, even if you do not use OneDrive, they are still stored there.