Here is the full list of all 20 Donut County achievements. It takes around 2-3 hours to unlock all of the achievements on Windows.
Lose the boss fight.
Complete the Trashopedia.
Complete the boss fight without taking damage.
Make Chef's secret soup recipe.
Destroy Trash King's monument.
Break into the vault at Raccoon HQ.
Destroy Trash King's monitor.
Find Trash King's secret getaway vehicle.
Fly through the donut hole.
Bring everyone back from underground.
Hack into the mainframe.
Win the boss fight.
Destroy Raccoon Lagoon.
Destroy the donut shop.
Break 3 dozen eggs.
Stock up on gamer fuel.
Quack 100 times.
Finish Gecko Park without collecting the radio.
Set Pepper's trailer on fire.
Release the hot air balloon.