Birth to potty kits are a rip off - they only fit 9lb+ babies, might not suit your baby at all, and you won't get 12+hours out of one over night.
Try various brands and types to find what suits you. I have 20ish AIOs of various brands for daytime and 10 fitteds for night time (ds wakes for a change when teething) and wash every 3rd day.
During the day, aim to change every 3-4 hours. For us that's a TotsBots EasyFit or Bambino MioSolo with a booster (mioboost in miosolo, bamboo in bamboo ef, hemp in minky ef) At night, a bamboo fitted with a hemp and a microfibre booster lasts 12+ hours (except when teething). That needs a separate cover, ds likes wool trousers (longies) but other people use a pul nappy wrap or fleece. Best to try a few different things to see what suits you.
You'll also need a lidded bin - mine lives in the bathroom next to the loo, handy for flushing poo away, then i keep a zip up wet bag in the lounge for ease - with a mesh bag to use like a bin bag. Modern nappies degrade if soaked so just keep them in the bag and shove them in the machine when you come to wash day.
Fleece liners wick moisture away from baby's bum. From weaning, flushable liners are good so you can just lift the poo out and flush.
99p shop baby flannels make excellent reusable wipes - they go in the wash with the nappies and will save £££££
Wash at 60* to kill bugs but use a scant tbsp powder - no softener - as it clogs up the fibres and messes with the absorbency. Most people i know do a prewash and at least one rinse on top to remove the soap. UV is a natural antibacterial so line dry outside where possible