The Sovereign Queen Elizabeth II
Governor General (the Queen's representative in New Zealand)
Parliament is made up of The Sovereign and the House of Representatives. The House of Representatives is made up of the Members of Parliament. The job of Parliament is to make the laws.
A Government (also known as the Executive) is made up of members of the House of Representatives appointed by the Governor-General as Ministers of the Crown. The role of the Government is to administer the laws.
The judiciary (the Courts) interprets the laws made by Parliament.