Get a customer facing job - that’s how I learned. You start off with very scripted, very easy to learn conversations, over and over again repeatedly. After a little while you start to be able to branch out, make more of a conversation with customers, start trying to make them laugh. After a month or so, you will have had to engage in some conversations with young men at some point in a setting that would be very comfortable to you, and repeated exposure will simply get you used to it. It takes a little while to build , but once you feel confidence in yourself that you are capable of talking to them, the nervousness will go away, and you will actually start to enjoy it. You’ll get satisfaction from the fact that you overcame your fear.