How do I get into an old Apple ID
How do I regain access to my old Apple ID
Question marked as
Why can't you access the old ID? If you forgot the old ID, see if you can recover the ID/password. Use every email address you can think of.
Apple ID - How to find your Apple - An iCloud e-mail address is an Apple ID.
If you forgot the Apple ID (iCloud) password, enter the Apple (iCloud) ID, and click Forgot Password. See if you can get a Rescue or Notification email option if necessary. Link to contact Apple Support at the end of the 2nd article.