1. On your mobile device, go to Settings > Passwords & Accounts

Passwords and Accounts

2. Select Add Account

iOS Add Account

3. Select Exchange

iOS Exchange

4. Enter your email address and provide a description for the account

Email Address and Description

5. Select Sign In to begin setting up your email account

Account Setup Sign In
6. Enter your email credentials and click Sign In

Enter Email Credentials
If you have Multi-Factor Authentication (MFA) enabled on your account, you will be prompted to provide the MFA code (this code will be sent to your mobile device).

Enter MFA Verification Code

7. Select the items to sync and the retention period (Mail Days to Sync)

Items to sync and retention