What is the name of the domain?
constellations.live
What is the error number?
None
What is the error message?
None
What is the issue you’re encountering
Can’t locate incoming & outgoing mail server info.
What steps have you taken to resolve the issue?
Google
What are the steps to reproduce the issue?
Hi! I’m technically challenged & looking to add my domain email from Cloudflare to the Mail app on iPhone. I need the incoming & outgoing mail server info (including host name, user name, and password) but can’t figure out what these are. Thanks for you help!
Welcome to the Cloudflare Community. 
Cloudflare Email Routing is just an email forwarding service. There is no Cloudflare domain email account that you can add to your MUA (Mail User Agent, aka your email app). There is no incoming or outgoing server provided by Cloudflare.
Since Cloudflare Email Routing forwards your email to an existing mailbox on another domain, that is the account that needs to be added to your MUA.
Details on how to configure your third-party email account to send email using your custom domain is something that you will need to work out using your email provider’s documentation.