To learn the AT&T email settings for Thunderbird, follow the steps below:

1. Go to Settings, then File, then Account Settings.

2. Choose an email account for updates, then select email settings.

3. Choose POP and IMAP from the section and enter the values correctly.

4. After adding the AT&T email settings, tap on OK and next. Finally, click Finish.

As a result, you have successfully configured AT&T email settings for Thunderbird.