If you are interested in learning English in one of New Zealand’s well-known English schools for 3 months or more, or study for a BA, MA or PhD degree, then you need a student visa.
In order to receive a student visa you have to meet health and character requirements and prove that the intention of your stay in New Zealand is genuine. You also need to include an “offer of place”,from a New Zealand education provider for an approved study program as well as, registration and payment approvals.
See links to more information about studying in New Zealand:
TOP 8 UNIVERSITIES IN NEW ZEALAND