You can add folders with content from your desktop (see Drag & Drop & Upload from Desktop). Alternatively, to help structure your files you can create Folders within the Node Drive environment yourself.
click the '+' situated on the right of the 'FILES' navigation title.
From the mini-fold-down-menu choose 'New Folder'.
Give the folder the name you want.
Adding a folder in the Drive Panel
You can later change the name by clicking on the name of the folder, or by opening the side menu by clicking on the three dots '...' next to the folder name and click 'Rename'.