I forgot my Apple id

See if he can recover the ID/password. Use every email address he can think of.

Apple ID - How to find your Apple  -  An iCloud e-mail address is an Apple ID.

Apple ID - Find  -       

If he forgot the Apple ID (iCloud) password, enter the Apple (iCloud) ID, and click Forgot Password. See if he can get a Rescue or Notification email option if necessary. Link to contact Apple Support at the end of the 2nd article.

Apple ID - Manage  -     

Apple ID – Forgot Password  *      

Tell him to check his web browser autofill entries and other records, or use Apple's iForgot service, or contact their Account Security team, or if you're the unit's original owner and have encountered the activation lock, click here and submit an unlock request.

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