Outlook 365 allows you to set up your email so that emails to you are marked "Focused" and marketing or mass emails are put into a filtered box (called "Other").  You can change this back to the standard view that Outlook had where mail was sorted by All and Unread by clicking on the view tab at the top of your Outlook and then clicking the "Show Focused Inbox" button.  This button will either be the same color as your tool bar or a darker grey color (signifying it is turned on).  When this select is changed, you will notice that the top of your inbox will say either Focused and Other or All and Unread as show below.