I'm assuming the bartender isn't the person he's interested in? If not then, unless the bartender is a friend, I doubt he/she would be all that interested in offering flirting advice. If the internet is available in your story then he might go and surf the web for flirting advice, but he might tend to get rather overwhelmed by all the largely conflicting advice available. He might just decide to go it alone and jump in with both feet, as it were. And if he's bad at flirting then he might come on too strong at first, especially if he feels he needs to compete with his brother, even if the competition is within his own mind only. So he might get told off by her, causing him to slink away and contemplate giving up. But if he's determined, he might come back another time and just be honest that he likes her, etc etc.
That's my idea, anyway.
