How does Holden try to order a drink even though he is underage?

In J.D. Salinger's "The Catcher in the Rye," Holden Caulfield attempts to order a drink at a bar in New York City despite being underage. He tries to appear older by adopting a more confident demeanor and wearing a casual, adult-like attitude. However, his nervousness and inexperience ultimately reveal his youth, and he struggles with the bartender's skepticism. This moment underscores Holden's desire to fit in and escape his adolescent insecurities.