Question

Do you the know that man? do you know him?​

Answer 1

ты знаешь того мужчину?

ты знаешь его?

Answer 2

I don't have access to personal data about individuals unless it has been shared with me in the course of our conversation. I am designed to respect user privacy and confidentiality. Therefore, I don't know the identity of the person you're referring to unless you provide me with more context. Is there something specific you'd like to know or discuss about this person?