“Ah don’t worry man. You’ll find someone. I feel you / I’ve been in your position for so long. There was this girl/boy that I liked... tell story”

Ask questions but make sure they don’t come off as inappropriate/ too nosey. It depends on the dynamics of the conversation/ how open the person is and is willing to share / how well you know them.

Sometimes silence speaks more than words. Maybe he went through a recent breakup or lost their SO or he’s feeling down that he’s never been in a relationship. There could be a thousand reasons. I’m curious why he didn’t ask “why?” after saying “no”. Maybe he didn’t feel like talking about it / was tired etc. Don’t draw any conclusions and don’t make any false assumptions. Read his body language — that could also reveal stuff.