What's "we're off" mean and when's it used?

Native speaker’s answer
Rebecca
"We're off" means we are going. So if you and maybe some other people are going somewhere, when you start moving in the vehicle, by foot, or another mode of transport, you can say, "we're off". Or, if you're leaving a place and want to let people know that you're going right now, then you can "we're off!" Ex: Alright, we're off to see the dentist. Ex: The race is about to begin... and they're off! Hamilton moves swiftly around the corner. => motorsports commentary Ex: We're off. Please remain seated with you seat belts fastened for the beginning of the flight.