There is more than one way to use the FTP protocol. Besides using an Internet browser, you may also use the ftp program on the command line. It is common for many ftp sites to allow anonymous logins. You would now be logged in. Once in you can use the commands cd, dir, and get to maneuver through the filesystem and retrieve the files you need.
More information is available in the ftp manual page.
It's usage is similar to ftp. See their respective manual pages for more information.