The user can set a PATH variable at a command-prompt that will override the system-wide PATH variable, even if the user doesn't have "Administrator" rights. The change will take effect for new processes the user starts from that command prompt.
For Registry follow below steps:
Click Start or press the Windows key. In the Start menu, either in the Run box or the Search box, type regedit and press Enter. In Windows 8, you can type regedit on the Start screen and select the regedit option in the search results. In Windows 10, type regedit in the Search box on the taskbar and press Enter.