There are several options for managing your Files and Folders from the Sidebar.
To hide the Sidebar from your view click or click the same icon to restore
Each folder also includes an Actions menu that allows you to take Actions on that Folder as well as an option to Expand All and Collapse All folders and subfolders
Other Folder Level actions from the Sidebar include: Rename, Download, Move, Duplicate, Favorite/Unfavorite, Mark as Read/Unread, User Permissions, Folder Settings and Delete. You may see all or a combination of these depending on your permissions.
or click the same icon to restore