How do you talk with users to build a product they really want?

That's a very classic question. Though I still haven't figured out yet how to do that. I'd like to build a product, that people really want. But every time I think about asking people what they want, I feel like exposing too much of my ideas, or I don't know what to ask. How do you proceed? Do you do a landing page explaining your project then asking people "are you interested?"? Or do you ask some questions that help you understand the user's needs? I know it's a basic question, but I feel like it can be very easy to start building a product people don't need. Thanks a lot 😃 !