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.
Find Trash King's secret getaway vehicle.
Bring everyone back from underground.
Win the boss fight.
Hack into the mainframe.
Destroy Raccoon Lagoon.
Destroy the donut shop.
Break 3 dozen eggs.
Stock up on gamer fuel.
Quack 100 times.
Set Pepper's trailer on fire.
Release the hot air balloon.
Complete the Trashopedia.
Finish Gecko Park without collecting the radio.
Complete the boss fight without taking damage.
Lose the boss fight.
Destroy Trash King's monitor.
Destroy Trash King's monument.
Make Chef's secret soup recipe.
Fly through the donut hole.
Break into the vault at Raccoon HQ.