Instructions cover iPads with iOS 11 or later.
Inthe left panel, tapDisplay & Brightness.
In theDisplay & Brightnessscreen, tapAuto-Lock.

choose the option you prefer.
Choices are 2, 5, 10, or 15 minutes.
you’re free to also chooseNever.

ChoosingNevermeans the iPad never goes into sleep mode automatically.
Which Auto-Lock Setting Is Right for You?
If the iPad goes into sleep mode while you are using it, set the delay to 5 minutes.

While three extra minutes doesn’t sound like a lot, it more than doubles the default setting.
Instead, set a timer for how often the passcode is required.
In thePasscode Lockscreen, tapRequire Passcode.

Don’t see these options on the screen?
If you haveiPad Unlockturned on forTouch IDorFace ID, you’ve got the option to’t delay the interval.
Instead, rest your finger on theHomebutton or raise the phone and look at it to unlock the iPad.

In theRequire Passcodescreen, select a setting fromImmediatelyup to4 hours.