You can add a folder containing multiple files to an existing project using the Add Folders option on the Project Files tab.
To add a folder to a project:
In the Current Project view, click Add Folders on the Project Files tab.
note:
To activate the Current Project view, you must first open a project. Click on the Sidebar and select a project from the Project List view, then click .
Browse to the folder, select it, then click Select Folder. During the import process, you might be asked to define conversion filters for unknown file types.
View the statistics about the added files on the Files Report dialog, then click OK.
on the Sidebar and select a project from the 
.