Allow your iPad to be opened without a PIN or password.
If you don't want to use a passcode to unlock your iPad, and you are one of those unfortunate people where the fingerprint or face ID doesn't work, you can turn that function off completely, so the iPad will just wake with no security.
Obviously, this is a potential privacy issue, although the iPad still wants a PIN for important functions, like erasing, etc, it does mean anyone with access to the iPad can read your email, check your open web sites and history, etc.
So only do this if you really need to...
Open Settings app. Tap "Touch ID & Passcode". Enter current PIN to unlock. Tap "Turn Passcode Off". Tap "Turn Off" when warning appears. Enter current passcode again, or Apple ID passcode if requested.