"Some people may not know you at your new online class, so you should turn on your facecam."

Does this mean that the person knows that there will be some people at the online class that knows you, but also knows that the rest may not know the person, and because of that, the person who said that thinks that the person should turn on their facecam?


That's about right, except he does not really say that some people will know you. He put it delicately. The alternative is something like "Some or all of the people at your new online class may not know you …", and that is awkward and unnecessary.