Here is the full list of all 22 Flying Neko Delivery achievements.
Complete the tutorial
Meet a villager
Meet all villagers
Gain maximum hearts with a villager
Gain maximum hearts with all villagers
Open a portal to a new world
Open portals to all worlds
Get a charm
Get all charms
Complete the Witchypedia
Get a new pair of robes
Craft food or drink
Get a new broom
Unlock a new paint
Win a race
Win all races
Earn 1M moons
Add 24 decorations to the cottage
Travel 250,000 units
Deliver 50 packages
Forage 40 unique ingredients
Earn the deed to your cottage