A forgotten or unknown iPhone/iPad passcode cannot be recovered - and neither can it be reset or modified from another device. If you see a waiting period you can wait and try again to input the correct Passcode; otherwise, the iPad must be restored.
Be aware that your iPad has an encrypted filesystem - and by design, it is designed to protect your data from compromise by a third-party. The key to accessing or recovering data from the device is knowledge of the Passcode - as this unlocks the iPad's Secure Enclave within which the only copy of the encryption keys required to decrypt your data are stored. Insofar as the system architecture is designed, if you don't have knowledge of the correct Passcode, locally stored data is permanently beyond reach.
For the bona-fide owner, data can be restored from your backup. If you haven't created a backup - all locally stored data will be unavoidably lost. That said, and data synchronised with iCloud (i.e., is not exclusively stored on the device itself) remains accessible with the associated AppleID credentials. If the AppleID credentials have been forgotten, with limited exceptions, they can be recovered.
You may find this support page to be helpful:
If you see an iPhone or iPad unavailable message or Security Lockout screen - Apple Support
iOS/iPadOS 15.2 or later with a forgotten Passcode
Apple has introduced a procedure with which to reset an iPad or iPhone with a forgotten Passcode - allowing you to use your AppleID and associated Password to reset your device.
How to reset your iPhone, iPad, or iPod touch when you forgot your passcode - Apple Support
You will be able to restore data from a pre-existing iCloud backup without the use of a computer, but will require a PC/Mac to restore data from an iTunes backup.
iPadOS 15.1 and earlier - and all devices that are Disabled
If your iPhone/iPad indicates that it is disabled/unavailable/locked-out, or you have forgotten your iPad passcode, you have no alternative other than to follow this process:
If you’ve forgotten the passcode on your iPad, or your iPad is disabled – Apple Support
You’ll need access to either a Windows PC (with iTunes for Windows installed) or a Mac (with iTunes or Finder - as appropriate for the installed version of macOS).
Download and use iTunes for Windows – Apple Support
Update to the latest version of iTunes – Apple Support
Use of a PC or Mac is unavoidable. If you don’t have access to a suitable computer of your own, that of a helpful friend or family member will suffice. Alternatively, the technicians at the Genius Bar of your local Apple Store will be delighted to assist:
Genius Bar Reservation and Apple Support Options - Apple
AppleID
You may also need your AppleID and associated password. If these have also been forgotten, they can be recovered here:
https://iforgot.apple.com
To recover your credentials, you’ll need access to one of the following:
- Your primary email address mailbox that corresponds with your AppleID
- Any of the secondary/recovery email addresses that should be configured for your AppleID account
- Any of the trusted telephone numbers (fixed line or Cellular/Mobile) that are associated with your AppleID
More information about recovery of your AppleID and associated Password:
If you forgot your Apple ID - Apple Support
If you forgot your Apple ID password - Apple Support
