Unlock iPad with Face ID
If you didn’t set up Face ID when you set up iPad, see Set up Face ID on iPad.
On supported models, tap the screen, then glance at your iPad.
The lock icon animates from closed to open to indicate that iPad is unlocked.
Swipe up from the bottom of the screen to view the Home Screen.
To lock iPad again, press the top button. iPad locks automatically if you don’t touch the screen for a minute or so. However, if Attention Aware Features is turned on in Settings 
> Face ID & Passcode, iPad won’t dim or lock as long as it detects attention.