There are three recognized languages, English, Te Reo ("the language", spoken by the Māori) and New Zealand Sign Language. Te Reo is the language of the indigenous peoples. It is widely spoken by many and incorporated into kiwi slang. Te Reo is used for public speeches, signs and other informative resources.
They use the New Zealand dollar. Their $1 is a coin with a kiwi bird on it!
A bottle of water costs $2.30 NZD, which is about $1.66 USD.
The best New Zealand food I tried was kumara (sweet potato) fries. Kumara has been grown by the Māori for hundreds of years and is an important crop for New Zealand's economy. The weirdest thing I tried was "chip sandwiches". Our global leader took us to get local fish and chips, but we stopped for some white bread, "tomato sauce" (ketchup) and butter on the way. She instructed us to put butter on the bread, load up some fries and smother it in ketchup! It was surprisingly good.