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.
Really beat the game.
Complete the world map.
Complete the garden.
Complete the mountain.
Complete the cavern.
Complete the abstract area.
Complete the space area.
Find an orb.
Beat the game.
Complete the forest.
Complete the ruins.
Complete the forest of fall.
Complete the solitary isle.
Complete the lake.