On Windows 10, I was able to search for set path environment variable and got these instructions:
- From the desktop, right-click the very bottom-left corner of the screen to get the Power User Task Menu.
- From the Power User Task Menu, click System.
- In the Settings window, scroll down to the Related settings section and click the System info link.
- In the System window, click the Advanced system settings link in the left navigation panel.
- In the System Properties window, click the Advanced tab, then click the Environment Variables button near the bottom of that tab.
- In the Environment Variables window (pictured below), highlight the Path variable in the System variables section and click the Edit button. Add or modify the path lines with the paths you want the computer to access. Each different directory is separated with a semicolon, as shown below:
C:\Program Files;C:\Winnt;C:\Winnt\System32
The first time I searched for it, it immediately popped up the System Properties Window. After that, I found the above instructions.