Add your email account to the Mail app on iOS devices

Open your iPhone or iPad's Settings.
To add your Microsoft 365 account, tap Mail, then Accounts.
Tap Add Account.
Tap Microsoft Exchange.
Enter your Email and a short Description (like your company's name or email type), and then tap Next.
Tap Sign In to confirm you want to use your Microsoft Exchange account.
Enter your Password and tap Sign In. (You might need to choose your account type as a Work or School to continue.)

Note: If Microsoft can't find your account, you might be asked to enter your details manually:

• Email: Your Microsoft 365 email address
• Password: Your Microsoft 365 email password
• Server: outlook.office365.com (this is required)
• Domain: This can be left empty
• Username: Your Microsoft 365 email address

Note: If you forgot your email password, here's how to reset it.
Tap Next. You might be asked to select Consent on behalf of your organization. This allows Microsoft 365 and the Mail app to work together. Tap Accept.
Tap Save. You can come back and update settings here at any point.
If you've verified that your emails are all there in the new account, and are ready to remove your POP/IMAP account, still in Accounts, tap the email account, then Delete Account, and then Delete from My iPhone.