Inbox provides all basic functionalities of overseeing all your sent and received messages and abilities to archive and view old emails.
How to bulk archive or delete a lot of messages.
When looking at the inbox (located through the small envelope (icon) by your user name in the top right), you may select the top checkbox (marked in a red box below) to select all visible checkboxes and apply an "Action". The actions available include "Mark as Read", "Mark as Unread", and "Archive". To delete and archive them, you may select "Archive".