To use an iPad as a second screen on a Windows 10 computer, you'll need to use a third-party app like SplashTop.

Sometimes you just need a quick and easy way to connect a second monitor, without dealing with a whole new display. Apple's Sidecar feature lets you turn your iPad into a second display for the Mac, ...

You can use your iPad as a second display for your Mac through the Sidecar feature, which comes pre-installed.