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