Windows Accessibility

Pressing Windows + U opens the Ease of Access settings. These settings give lots of tools and options to make your PC more accessible, based on your needs. The settings include Narrator, the in-built screen reader, the Magnifier, Keyboard and Mouse settings, Closed Caption settings, Colour and High Contrast settings, etc.
You can also start Narrator directly by pressing Windows + Control + Enter.
And you can start Magnifier directly by pressing Windows + Plus sign (and Windows + Plus or Minus sign will zoom in or out respectively).
To close the Narrator or the Magnifier, focus on them using Alt + Tab, and press Alt + F4.