Well, it depends on how you're accessing CC. If you're on a computer or laptop then, yes, you will need Flash for your browser, and make sure it is up to date. If you are on a phone or tablet that is Android based check the playstore for the CC app that allows you to use the chat rooms. Phones and tablets, by default, do not support Flash and therefore can't be used to access chat.
Lastly you may want to start posting these in Misc rather than New Users. I see you posting frequently here and it's not really the appropriate place. If it's related to using the site you can post in the User2User Tech forums for questions.