Office 365 is a cloud-based suite of productivity apps like Outlook, Word, PowerPoint, and more. microsoft365.com/setup is a bundle of services including Office 365, plus several other services including Windows 10 Enterprise. On an Android phone, go to the Play Store, search for Outlook, and install the Outlook app. Open the app and tap Get Started. Enter your Microsoft 365 email address and password, and tap Sign in. Optionally, you can add more accounts, or tap Skip. It's a free app that will be preinstalled with Windows 10, and you don't need an Office 365 subscription to use it. The existing My Office app has many of these features, but the new Office app puts the focus on the free online versions of Office if you're not an Office 365 subscriber.