Here is the full list of all 27 Through the Woods achievements. It takes around 3-4 hours to unlock all of the achievements on Windows.
Relieved Garm from his pain
Complete chapter 5
Complete the game!
Killed by a troll
Killed by Huldra
Killed by Særimne
Killed by one of the brothers
Killed by a draug
Found all collectibles
Read all texts
Found all folklore items
Found all abandoned children
Found the Red Hood
Complete Erik's Cabin
You need two to make a pact
One was the king who won, two were defeated
Found all dwarven gates
Found the little heroes' toys
I live, I die, I live again
Found Pesta, the plague maiden.
Completed chapter 0
Completed chapter 1
Completed chapter 2
Completed chapter 3
Complete Chapter 4
Opened all doors
Found all reflectors