How does winning the Play-Writing Competition change Father’s perspective of Adeline? And what does he allow Adeline to do which is uncommon for girls within a Chinese home during that time?

Father sees "success" through a very narrow lens. Winning the writing competition fit within what father valued. He feels validated, although he had nothing to do with it, by his daughter's success. He lets Adeline travel to study in England which was not a common thing to happen for a girl.