New zealand has a parliamentary democracy but with a constitutional monarchy. The queen of United kingdom serves for New Zealand too. She is represented by her general in New zealand. A bill or law can be enacted by the house of representatives. The bill becomes a law only after the assent of the queen or her general.
The governor general performs the role of delegating the majority party to form the government. The house of representatives make laws , policy making, spending. administrative decisions etc. It is the only law making body( single chamber).