Here is the full list of all 17 GRIS achievements. It takes around 6-8 hours to unlock all of the achievements on Windows.
Finish the game
Fifth stage
Memories from the past
Find all mementos
Sing to the magic fowls
Avoid eel bites
A color has been brought back
Fourth stage
Third stage
Feed the forest friend
Break the stone piles
Second stage
Avoid the storm
First stage