The Python installer for Windows doesn't use the optimal default settings. Follow these instructions when running the installer. If you have already installed Python with the default settings, follow the instructions here instead: add Python to the PATH variable
- Check the Add Python to PATH box
- Choose the Customize installation option
- Keep the default settings and click Next
- Check the Install for all users box
- Customize the install location: C:\Python39 or whatever version number you're installing
- Click Install