Hi There, as far as I am aware there is no specific COVID grants so you would have to apply as a new start-up to a lender.
Although challenging in the current environment not impossible. Personally I advise you seek out some advice on your target market and a simple cashflow so you can understand what revenue you need to generate to be financially viable.
There is lots of support in other ways with your local economic development agencies such at AtEED and ChristchurchNZ. Also it could be worth looking up Ministry of Awesome (MOA) they have great resources for start-ups.
If you want some more specific advise then feel free to flick me an email at email@example.com