How can I add a device to my list of devices

First you need to find his ID and Password. Forgot user ID: https://iforgot.apple.com/appleid#!&section=appleid

Forgot password: https://iforgot.apple.com/password/verify/appleid

Then to change the ID: Change your Apple ID - https://support.apple.com/en-us/HT202667

This reply does not answer the original question: How do I add a device to my list of devices? I have too many Apple IDs that I created in the very early days of Apple IDs that I cannot keep track of nor can I find all of the old ones under which I bought Apple software from the Apple Store.

Now I recovered an old Apple ID associated with my Apple Mini and I want to add my Apple MacBook and Apple iPod Touch to the list of devices under this single Apple ID.

How do you add a device to a list of devices under an existing Apple ID? I am signed in to this Apple ID, which lists my Apple Mini as the only device, from my MacBook that I want to add to this device list.

I need to add a minipad to my current account.