You can easily add your business email account to your iPhone’s Mail app by following the steps below.
From your home screen, tap Settings.
Scroll down and select:
Passwords& Accounts
Tap Add Account
Select Other
Tap Add Mail Account to begin the setup.
Fill in your account information:
Name
Email address
Password
Description (optional)
Then tap Next.
Under both Incoming Mail Server and Outgoing Mail Server, use the following host name:
Host Name: mail.enter-system.com
Enter your email username and password as required.
Once submitted, your iPhone will verify the settings and add the mailbox to your email accounts list.