re: "After that I have ID verified my account with my own face can I change my profile picture to someone else's just for privacy reasons?"
Freelancers who want to maximize their privacy don't use Upwork. Privacy is not this site's purpose. Freelancers use this site in order to maximize their ability to find freelance work with clients all over the world.
If you don't want to have your photo online, then don't set up a freelancer profile here. Use Upwork only as a client, or use other platforms with less stringent requirements, or stay offline entirely.