By default, no FTP server is installed. But you can use SFTP which comes standard with the SSH protocol, you do not have to install anything on your server.

To connect to SFTP, you could either use the terminal or a FTP client. We recommend using Coda 2 or Filezilla.

Normally, you would not have to enter a password because you authenticate with your SSH key. This can be done with any FTP client basically, you can authenticate with your SSH key file.