Crushes??

How do you know when you have a crush on somebody? I believe I like girls and guys but looking at either I don’t really think “ oh that person is cute, I want to date them”. I see girls and think there pretty (some prettier than others). Guys used to be attractive but now there not, I can tell there not ugly but there not cute to me. I don’t know if I making sense but I need help. Every person I’ve liked I fell for them after talking to them rather than appearance. What am I??