It depends which server you will try to connect and how you will try to connect.
If you are using an FTP program (Example: WS_FTP), it came with documentation on how to use it. Most FTP program has documentation
Port # depends on what the server provides. If you are downloading from an FTP, a browser should do that for you. If you are uploading via browser, your browser should allow it too as long as you allow the connection. An FTP program like WS_FTP needs the info you need. Check with the programs documentation.
See samples at http://www.ucc.ie/doc/other/howtoftp.html
I can't connect to the ftp server. I want to ask how should I fill up the form here?
Site name: like what?
Host: like what? Port: what should I use? Directory: like what? User name: Password: * Passive mode what is it for?
URL: like what?
Can show me some of the example?