For example. You came your home with your best friend and your friends turned the light on. they prepared birthday party for you. But you didn't know it. You asked your best friend "Did you know this surprise? For example. You can drive car. People ask you "Do you know how you can drive car?" We can use "Do you know?" in present questions. But we can use "Did you know"? when the time is important.

When asking someone if they have previously heard about a piece of information, you ask them "Did you know that....". For example, "Did you know that it is physically impossible for rabbits to throw up?" Weird example, I know. (: Usually when people say this they believe that you don't know the information that they are asking you about. When people ask "Do you know" they are usually wondering if you know about a particular person, place, thing, or fact. For example "Do you know that there is a new restaurant opening up downtown?" or "Do you know the name of the new employee at our company?" In these situations, the person is asking you for information about someone or something or they are wondering if you have previously heard about someone or something. I hope this helps!