thanks Keith, I will give this a run through later on 🙂
is your Snowberry-child theme’s folder located in the correct place/folder,
ie wp-content > themes
(you mentioned at the start you had created it in the back up folder which is incorrect and thus would not show the theme available in your dashboard to activate).
Your own domain emails are set up via your control panel with your web hosts. So for johnny@mysite.com you will need to login to your web hosts for your mysite.com domain and set up your email address from there.
WordPress has no role in setting up or configuring your emails.