Question

what would be an example of foreshadowing in a story about a girl who fails to get a part in a play she wants

Answer 1

If the girl messes up her lines and sees the director write something down you could assume that the director does not want her to be in the play because she messes up her lines

Answer 2

Foreshadowing is a subtle event that happens to almost show what might be coming later in the story, an example of this could possibly be the girl accidentally messing up a costume or forgetting to memorize a line and does not go back to memorize it.