Login to DirectAdmin and choose the “File Manager” link from the “System Info & Files” section.
Within the "domains" folder you will find individual folders that pertain to each domain being hosted. Within each of these folders you will find a unique "public_html" folder that will hold your website files for that particular domain.
To upload files to the server using the DirectAdmin File Manager, navigate to the destination where you would like them to reside. Using the File Manager, click on "Upload File" Button found at left bottom side, select the files from your PC using the form fields provided and choose "Upload". (*Please Note: When you are on the File Manager page within DirectAdmin, the Help Button at the top of the page will provide detailed assistance for how to use the File Manager).
*Replace domain.com with your actual domain name.