Hi there and welcome
To set up your email account on your iPhone, please do the following
Incoming Mail Server
Host Name — mail.example.com (replace example.com with your actual domain name.)
Username —***@******.*** (the email address you’re accessing.)
Password — Password ***** the email address. If you don’t know what this is, you can request it from the (Panel > 'Mail' > 'Manage Email') section of your panel by clicking edit for the address.
Outgoing Mail Server (SMTP)
You should then be able to send and receive emails on the iPhone.
Let me know the results please.