You can upload files and create subfolders into the Folder tool easily. 

To upload new files to the Folder, click on the 'file upload' button under  'New...', the upload field will appear, where you can either drag the files to, or browse the files that you want to upload. 

The files then will be automatically uploaded. 

You can also create subfolders in the Folder tool to make file storage more organized. To create a new subfolder, go to the Folder tool, and in the 'New...' menu click on the 'subfolder' option. Type in the name of the new subfolder, where you can upload files. 

You can create a bibliography, if you select 'book' under the 'New' menu, and either fill out the details of the books manually, or type in the ISBN number of them, and the system automatically fills out the information about the book.  

You can also add meta-data and journal titles with the same method, and create a link collection of relevant external links.