If you want to post a new message, you have two options :
*you can create a new subject, in which case you click on "nouveau" or
*you can reply to someone else's message, in which case you click on "répondre".
Once you've written your message, you can click on "prévisualiser" to have a preview of what it will look like and when you're satisfied, you click on "envoyer".
If you want to quote someone, click on "citer" when on their message.
If there's anything else you want to know, don't hesitate to leave a post here, or you can message me directly (team "R.R.Corporation" on the game).