There's a quick start that's one-to-one chatting, but you want the "chat room" option
that is the link above. Name the room and provide a password and your chat
session should be good to go.
One cool thing I just heard someone say yesterday . . . they opened a chatzy
room for students to comment and question during a movie. One or two
students were given the room admin password and expected to moderate, and
the teacher was also a participant. How thought provoking is that!?