You need to add the directory you installed git to to your PATH environment variable.
- Right click on Computer.
- Click Advanced System Settings
- Click Environment Variables inside the Advanced Menu
- Under System Variables, scroll to PATH
- Add ;”C:\path\to\git\bin”;”C:\path\to\git\cmd”
Test the git command in the command prompt to see if it worked. Git is usually located in Program Files or Program Files(x86)