There is no such thing as a Thunderbird email account. Email providers provide email service. Thunderbird is email client software you installed on your computer. You uninstall it just like any other software. You need to cancel email service with your provider to close out an email address. No one is going to call you. Answers are!placed in this forum.

Er, I don't think you have a "Mozilla Thunderbird e-mail account". Mozilla doesn't issue email accounts.

What do you have to the right of the @ in your "thunderbird account" email address? Knowing that will allow someone here to advise where your account came from.

You could just uninstall Thunderbird. The account will in all probability die if left unused.

I get spam in my gmail accounts. Don't expect this change to be a cure-all.

You could work your gmail account through Thunderbird. So you could add the new gmail account to Thunderbird. Personally,I can't abide the gmail website.