In the Outlook Taskbar your tasks will be listed for all the mailboxes you have attached to your Outlook, so this will include shared mailboxes and your own mailbox.
You can group these by mailbox to make them easier to view.
in the Task bar, click on:
select View Settings
Untick Automatically group according to arrangement
In Group items by
select Recipient Name
then click Ok and Ok again to close the Advance View settings window