How your mailboxes work
The mailboxes connected under your own name, and the folders inside each one.
My Mailboxes lists the mailboxes connected under your own name. Where a shared inbox is answered by a team, these are yours: nobody else sees what is in them.

What is inside one
Expanding a mailbox reveals its real Outlook folders. TeamEmail does not invent them or rename them, so what you see here is what you would see in Outlook itself.
- InboxMail as it arrives, in the order it was received.
- Sent ItemsEverything you have sent from this mailbox.
- ArchiveConversations put out of the way, which return to Open if someone replies.
- Junk EmailMail Outlook has flagged as spam.
- Deleted ItemsMail you have removed from another folder.
How it differs from My work
A folder here is a place mail physically sits. My work is a view across mailboxes, built from what is assigned to you or what you follow. The same message can appear in both, and reading it in one marks it read in the other, because there is only ever one copy.
Connect another mailbox from Settings > Connections.