Here is the full list of all 42 Only You achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
12 Lvl completed
End Game
Music 12
Last Step
First Restart
Game Over
11 Lvl completed
Music 11
10 Lvl completed
Bandit 1 Dead
Bandit 2 Dead
Bandit 3 Dead
Music 10
9 Lvl completed
Music 9
8 Lvl completed
Music 8
7 Lvl completed
Music 7
6 Lvl completed
Music 6
Mute
Middle Game
First Death
5 Lvl completed
Music 5
4 Lvl completed
Music 4
1/3 of the game
3 Lvl completed
Music 3
2 Lvl completed
Music 2
Pause 2
Pause
1 Lvl completed
Jump
Go Right
Go Left
Music 1
Fall
Start Game