If you're planning to study here full time for more than three months you'll need a student visa.
Student visa requirements include:
If you’re spending six months or more here in New Zealand you may need to be screened for tuberculosis.
If you’re over 17 and intending to be in New Zealand for over two years, a police certificate will be required to show that you are of good character.
If your course is three months or less, you don’t need a student visa: just a visitor visa.
If you have been offered a place in an approved exchange scheme you can apply for a student visa for the duration of your exchange, provided you meet our health and character requirements and are a genuine exchange participant. If you’re coming on a working holiday scheme you can do one or more courses of study as long as their total duration doesn’t exceed six months.
This is just a summary. You should make sure you get the full details at Immigration New Zealand.
If you wish to stay in New Zealand and work after you have finished your studies, you will need the right visa.
International students who have achieved a New Zealand qualification may be allowed to gain experience in work related to their studies.
Depending on what you study, you may be able to work in New Zealand for up to four years, and possibly even gain residence.
First you need to apply for a visa and have it approved. The study to work pathway has two steps:
After your post-study work visa (employer assisted) you may qualify for a New Zealand resident visa under the Skilled Migrant Category. If your work is in an occupation that has skill shortages, this improves your chances of being allowed to stay, either with work visas or residence.
Whatever visa you apply for, you will need to pass health and character checks.