Here is the full list of all 18 Baba Is You achievements. It takes around 25-30 hours to unlock all of the achievements on Windows.
Complete a secret area.
Find an orb.
Really beat the game.
Complete the world map.
Complete the mountain.
Complete the cavern.
Complete the abstract area.
Complete the garden.
Complete the space area.
Complete the forest.
Complete the forest of fall.
Beat the game.
Complete the ruins.
Complete the solitary isle.
Complete the lake.