This is a rather loose adaptation of a traditional Vietnamese recipe, often used as a filling in Bánh Mì. You can google for lots of variations. Đồ Chua is often made as a vinegar pickle, with added sugar – this recipe is a keto/paleo & sugar-free lacto-fermented version.
The basic idea is to spiralize (or grate) & mix everything, except the chilies. Then pack all the spiralized vegetables into jars, with the halved chilies slid down the side, topped up with brine.
Start by making the basic brine and leave to dissolve while you prepare the vegetables.
Important to measure carefully. This is the brine I use for most simple ferments, unless I find a recipe that has a good reason for using something different …