Microsoft has published certain Guided Walkthroughs helpful for us when working with Exchange, Outlook, Office 365 (o365) etc. to set up mailbox, calendar etc. Very helpful in learning and troubleshooting instances:

Following are the guided walkthroughs available:

• Sharing calendar and contacts in Office 365
• Setting up a mailbox that multiple users can access and use in Office 365
• Sending email from another person’s mailbox or from a group in Office 365
• Accessing other people’s mailboxes in Office 365
• Creating and managing resource mailboxes (conference rooms/equipment) in Office 365