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