Apple password
I do not know my Apple ID/password and have an old email.
iPad, iPadOS 13
Question marked as
To find out exactly, which Apple ID you have used, check the steps in this article:
If you forgot your Apple ID email address or phone number - Apple Support
The password can be reset:
If you forgot your Apple ID password - Apple Support
If all fails, you'll have to use the Account Recovery, as explained here:
How to use account recovery when you can’t reset your Apple ID password - Apple Support