The image below represents the active click area (in green) that will result in the selection of the file or folder.
When click on the name (on the name column), you will either be taken into the folder or if it was a file you clicked on, the file will open in a corresponding Viewer in the same tab.
Selecting Groups of Consecutive Files or Folders
To select a group of consecutive files or folders
Select the first file or folder you want (by clicking anywhere in the highlighted green area shown above).
Press and hold the SHIFT key.
Select the last file/folder you want.
Release SHIFT key and all selected files remain highlighted.
Multi-Selecting Non-Consecutive Files or Folders
To multi-select a group of individual files
Select the first file you want (by clicking anywhere in the highlighted green area shown above).
Continue to select files by clicking the check box (located in the first column).
The panel on the right will list all the files/folders in your selection.