Hello willwham1,
Thank you for your question regarding closing a domain, website, and email. If it is for an Addon domain, follow our guide on Deleting an Addon Domain. This will remove the site, domain, and email from your cPanel.
If you want to cancel your Primary Domain I recommend contacting Live Support with your request.
Be sure to cancel your domain registration, if it is registered through us.
Thank you,
John-Paul