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