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