You're looking at SSH (Secure SHell) commands, specifically "chmod", the command used to alter the file permission access. What "chmod 777 <file>" is doing is giving read, write, and execute permissions (the 7) to the File Owner, Group Members, and Users respectively. Likewise, "chmod 666 <file>" simply gives read and write permissions to each of the previous groups.

While getting used to SSH is a very good idea, you should be able to modify these permissions in your FTP client (like FileZilla), or maybe even the provided web-client.