Here is the full list of all 20 Carto achievements. It takes around 6-8 hours to unlock all of the achievements on Windows.
Complete the game 100%.
Visit the airship.
Finish snowman buddy.
Read all stories in the Story Chalet.
Finish the three levels of the Tower of Hanoi in the fewest steps.
Behold the legendary flame tornado!
Listen to the quartet of birds.
Find something mysterious in the lake.
Give a plant your full support.
Finish chapter 10.
Finish chapter 9.
Finish chapter 8.
Finish chapter 7.
Finish chapter 6.
Finish chapter 5.
Learn nothing about cactuses.
Finish chapter 4.
Finish chapter 3.
Finish chapter 2.
Finish chapter 1.