MX records are associated with server accounts. If you are paying Godaddy for a host account, they also have access to it. Puzzling. You may need to give much more info, but whatever the issue is, it doesn't seem to be on that relates to Thunderbird itself.

Do you own your own domain nane? If you want to see the MX records for your domain -- these records tell mail servers where to send mail addressed to you -- you can use a tool such as:

https://mxtoolbox.com/

If that doesn't sound relevant to what you are trying to do, what are you trying to do?