One example of conformity in the novel, Ender's Game, is Ender's parents' decision to sever all ties with family and friends in order to practice their religion without question. Ender disagrees with their refusal to conform believing that he would rather please others in an attempt to fit in.
Another example of conformity would be Peter's exterior persona..... the way he publicly conforms to societal expectations, even though he cannot control his violent tendencies in private.
Lastly, we have Ender. Ender conforms to the role he's been given to play in Battle School. He is not a murderer..... he is not a calculating machine of death, and yet, through his participation in Battle School and the manipulations of the adults in his life...... he becomes the murderer and plays the role.