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The device may remain activation locked anyway.

Turn off Activation Lock - Apple Support

If you don't sign out of iCloud before you put your device in recovery mode and restore, it might remain in Activation Lock. That means you need to enter the same Apple ID and password that you used when you previously set up the device.

Forgot your Apple ID or your Apple ID password?

If you have iOS 11 or later and your account is protected with two-factor authentication, you can turn off Activation Lock with your device Passcode. Tap Unlock with Passcode, then tap Use Device Passcode.

Without fixing access to your AppleID, you’re going to experience all kinds of grief and roadblocks in using your iPad. As a consequence, assuming that you are the owner of the device, you should initially concentrate your efforts on restoring access to your AppleID.

If you have forgotten your AppleID or associated password, they can be recovered here:

https://iforgot.apple.com

Once you have regained access, you can simply manage your AppleID account using a web browser:

https://appleid.apple.com