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