How do I Recongifure An XP Embedded Computer for other uses?

Have received an older computer, Compaq Deskpro, P600,SFF computer that that used by a business. It has Windows XP Embedded.

I can’t do anything but access old programs and data left on it by the store that was using it.

Cannot “right-click” to access any way to install or delete existing programs.

Is there a way to reconfigure this machine so it can be used?