How does William become a knight in the movie knights tale?

In the 2001 movie "A Knight's Tale", William Thatcher does not become a knight. He defeats Sir Ulrich von Lichtenstein in a jousting tournament and is offered the chance to become a knight, but he declines, choosing instead to return to his peasant life. He chooses to remain true to his origins, valuing his friendships and personal integrity over the prestige and recognition that knighthood would bring.