Instructions which allow you to choose your mobile device:

https://support.office.com/en-us/article/set-up-office-apps-and-email-on-a-mobile-device-7dabb6cb-0046-40b6-81fe-767e0b1f014f

Instructions for specific devices: 

For all of these devices, please select Exchange or Microsoft Exchange as the type of email account to add.

• Apple (iOS) Devices - https://support.microsoft.com/en-us/office/set-up-the-office-app-and-outlook-on-ios-devices-0402b37e-49c4-4419-a030-f34c2013041f
• Android Devices - https://support.microsoft.com/en-us/office/set-up-office-apps-and-email-on-android-6ef2ebf2-fc2d-474a-be4a-5a801365c87f