I don't use FTP so much now. For moving stuff to me web server I usually use webDAV. I do find it useful sometimes for moving things onto my 3DS, for this I use ftpd and GNU's basic FTP CLI tool, which is part of Inetutils. For anything fancier I've used FileZilla, and once upon a time CuteFTP (though it seems t ocost money now, so I'm not even gunna link it).

Basic commands for GNU's FTP tool:

• ftp to start. Then you get ftp's shell
  • ☞ Easier to start giving it the server to connect to ftp [server] [port] EG: ftp 192.168.0.20 5000
• From there can use standard linux commands to ls files and cd.
• To upload stuff use send [filename]
• To download use get [filename]
• quit to close.