Press and hold the Top button and either Volume button until the power off slider appears
Drag the slider to turn the iPad off
If the iPad doesn’t respond, press and hold the Top button and the Home button (iPad with Home button) until the power off slider appears
Drag the slider to turn the iPad off
To force restart (if it’s frozen), press and release Volume Up, press and release Volume Down, then press and hold the Top button until the Apple logo appears