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