I really think that you can add friends in Quizziz, that way you can chat with them anytime they´re online.
Here´s how I think it would work. You want to add a friend in quizziz, you enter the username of your friend and you send a code to him or her. That way, when your friend receives the request he tyes in the code you gave him. That way you can´t just make friends with everyone.
I hope you like my idea