Hi there – good question. Structure could be a range of options, from self-employed in your own name or under a partnership structure or a limited liability company. When you are early in the business, there is no issue with keeping things flexible, unless you are super convinced that you know your market, know the opportunity and are convinced with forward work that this is what you will be doing for the next few years. In which case, typically the easiest is to set up a Limited Liability Company – just google that, it is super easy to set up in NZ and you can largely do it yourself.
Regardless of structure, you will need a name, brand to sell/position in the market.
In terms of funding – there are not that many out there unless you are currently unemployed and/or on a benefit – check this out – https://www.workandincome.govt.nz/products/a-z-benefits/self-employment-start-up-payment.html