1. Go into the App Store / Play Store and search for Microsoft Outlook. Once installed, open the app.
2. Click Add Account.
3. Type in the email address and click Continue.
4. Complete the password and mult-factor authentication prompts.
5. Click Maybe Later when prompted to add another account.
Additional information:
It is recommended to turn off Focused Inbox so you don't miss any emails.
App updates can stop the account from picking up new emails, if this happens then deleting and re-installing the app and repeating the setup procedure should get everything working again.