The currency in New Zealand is the New Zealand Dollars (NZD). Notes come in the denomination of 5, 10, 20, 50 and 100 NZD, whereas coins come in the denomination of 10, 20 and 50 cents, 1 and 2 NZD.
It is always better to check the exchange rate before you get your forex. If you do not feel comfortable carrying cash right from India, you can get the same exchanged at the airports or at the banks in New Zealand. You also have the option of either carrying cash or even your credit and debit cards on your New Zealand trip. You can also use the ATMs in case of cash withdrawal. However, there may be additional charges attached to the transaction and it is always better to get the same confirmed from your bank.
Get in touch with an authorised agency like SOTC, who can clarify all your foreign exchange queries.