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.
Killed by Særimne
Found Pesta, the plague maiden.
Killed by Huldra
Found all reflectors
One was the king who won, two were defeated
Killed by a troll
Completed chapter 1
Completed chapter 0
Relieved Garm from his pain
Complete chapter 5
Complete the game!
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
Found all dwarven gates
Found the little heroes' toys
I live, I die, I live again
Completed chapter 2
Completed chapter 3
Complete Chapter 4
Opened all doors