Join anyway
If you don't have a camera, or you'd rather not turn it on, choose Join anyway. You still get into the room.
No camera? Join anyway
A camera is optional. You can be in the room, listening and watching, without sending anything yourself.
You'll see and hear everyone else
Their video and audio come through normally. Nothing about your setup changes what they send.
Your own tile says Camera off or Muted
That's expected — it's how the room shows the others that you're present without sending video or audio.
You can turn things on later
If a camera or mic becomes available mid-call, enable it and your tile switches over. Your browser will ask for permission the first time.
For a real two-way call, at least one side needs a working camera and mic — see What you need.