Here is the full list of all 31 Deadlight achievements. It takes around 12-15 hours to unlock all of the achievements on Windows.
Finish the Nightmare mode
Get 100% of Deadlight
Find all of Randall's memories
Beat the high score in Madness Mansion
Beat the high score in Sport Daisy
Find all the IDs
Make it to the end
Finish Randall's flashback
Reunite with Stella
Finish Randall's nightmare
Find Parker in the hockey arena
Beat the high score in Raven Thunder's Rock Legend
Push a zombie over a railing
Reload the revolver really fast
Face someone from Randall's past in the Park
Roll to avoid lethal fall damage
Follow the Ratman to his den
Finish Randall's dream
Tackle an enemy
Perform a headshot
Get to the military control
Find the first health expander
Reach the junkyard
Get infected by a friend on the leaderboards
Perform a combo on an enemy
Execute an enemy
Kill an enemy with a single melee attack
Tackle a door
Escape from the warehouse
Find a page of Randall's journal
Survive a close encounter