Delete I Pad from the device list of my accout?

Use the information in this document to check your Apple ID device list to find where you're signed in --> Check your Apple ID device list to find where you're signed in - Apple Support

- Learn which devices appear in your Apple ID device list, how to find your device's details (including if it's a trusted device), and how to remove a device.

- Special section at the end on how to "Permanently remove a device from your account page"

From settings of a device that you do have…:

Settings > [Your Name / AppleID]

From the device list, tap the name of the device that you wish to delete - then tap Remove from Account.