Set up Office apps for the first time:
Tap any Office app like Word to launch it.
Enter your email address and tap the arrow.
Enter the Password associated with your email address > tap Sign in.
Note: If you’re prompted to create an account, just add a password and then follow the prompts to verify your identity. If already have a Microsoft account, go back and sign in with a different email address.
Tap Start using Word to get started with the app.
If you have other Office apps installed on your Android device, your account and OneDrive files will be automatically added.
To add another account, tap Open (or Open other documents if you’re on a tablet) > Add a place.
If you are using OneNote, tap Settings > Accounts.
Choose the cloud service you want to add, such as OneDrive for business or Dropbox.
Enter your email address and password that you use to sign into that service.