I want to remove all this so that no one will look at what I do on the computer.

How to remove a link to a room? e.g. https://meet.jit.si/erihre. when after / I write at random. for example / airhoigiovegoegovi then why is my camera visible? How safe is this? And if a person guesses the link to my room, will he see me? I want to remove all this so that no one will look at what I do on the computer.

Then use it in incognito mode. All jitsi-meet does is stored in localstorage, for example if you set a display name, so next time you open you don’t need to do that, but if you open it in incognito mode, and when you close the last incognito tab/window all the information is lost.