Here is the full list of all 17 Path of Giants achievements. It takes around 4-5 hours to unlock all of the achievements on Windows.
Complete 12 levels without using undo
Discover the hidden treasure
Collect ALL the coins
Enter the hidden chamber
Break 7 pots in 3 seconds
Complete Winterfest
Find the sneaky coin in level 17
Complete any Winterfest island without using undo
Smash a distant pot in level 9
Find the Lantri!
Ride 30 elevators
Get unstuck after being stuck
Undo 12 times in a row
Get an explorer to say "Woo!"
Get onto a spinning platform that you control
Boost down on an explorer
Boost up on an explorer