The people on your team each need a user account before they can sign in and access their mailbox. The easiest way to add user accounts is to add them one at a time in the Office 365 admin center. After you do this step, your users will have Office 365 licenses, logon credentials, and Office 365 mailboxes.

Go to the 

On the Home page, choose Add a user.

Fill in the information for the user. Choose Add when you are done.

They’ll need to change their password after 90 days. Or you can choose to Make this user change their password when they first sign in.

After you add a user, you’ll get an email notification from the Microsoft Online Services Team. The email will contain the person’s Office 365 user ID and password, so they can sign in to Office 365. You need to tell your new user about their Office 365 sign in information. Use your normal process for communicating new passwords