Good luck man!
As someone that left the US a decade and a half ago, here's some things to go ahead and start getting answers to so you don't have to figure it out when the time comes:
- Figure out how to get a bank account (hopefully you've already worked this one out before arriving)
- Where to buy toiletries and medicine. Specifically deodorant. The UK is mostly spray deodorant where as I'm a stick deodorant person. At one point I was just bringing 4 sticks of deodorant back with me after every trip home. I'm not sure which way NZ leans but it was definitely something I hadn't considered before
- Where to buy socks and underwear you're comfortable with
- Figure out how the health service/insurance works. Go ahead and book dentist and doctors appointments 6 months in advance if possible so you get in the habit.
- Figure out how paying taxes works
- If you're a US citizen, remember you're still required to file taxes with the IRS every year.
- Learn how to make friends. I still haven't figured this one out. Let me know if you do.