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