You can make a account without a real email

You can do that with almost anything. This depends on the security and reliability of a server or website/platform. For example, most of the time you can fake an email for a random website, but you can't do the same for hotel wifi. lol

changeable lenses of different focal lengths allow light to enter the camera, which then forms the image on light-sensitive film" is the one among the following statements about working principle behind a basic still camera is true.