That’s like keeping the spare key for your car locked in your glove box.
If you really used an @build-interior.com email address, that domain isn’t configured for receiving email. There’s no MX record for it.
Cloudflare’s also not your web host. Just your DNS records, and website proxy.
You’re going to need to sort out your email issues first. And that’s going to have to be done with the help of whoever hosts your email. Just be sure that any new DNS records you add to get your email working need to be set to 
DNS Only.