what are two adventages that the boys at the interview had over ishmael?

What chapter are you referring to?

The other boys at the interview were all dressed appropriately, whereas Ishmael dressed casually for the interview. The other boys were also far more comfortable in their environment--like how they laughed when Ishmael didn't know how to use an elevator--and could probably speak English better than Ishmael. Other than that, Ishmael had the upper hand due to his knowledge and front-line experiences with war.