When you join chat rooms, those rooms are displayed near the top left of the main Paltalk window. They will be gathered into the 'active rooms' area.
You can be in up to five (5) chat rooms at a time depending on your subscription.
When you are ready to leave a room just hover over the 'speaker' icon in the active rooms area with your mouse. The icon will change from a speaker to a red 'X'. Click on the red 'X' icon to leave the chat room.