Here is the full list of all 45 The Forest achievements. It takes around 50-60 hours to unlock all of the achievements on Windows.
Play through entire game without killing or eating animals. Alone in Single Player or together in Multiplayer.
Pass 50,000 steps
Cut down 1000 trees
Finish Game
Find all missing passengers
Explore all caves
In Single Player, don't kill any cannibals for more than 10 days in a row
Kill 6 or more fish with a stick of dynamite. Alone in Single Player or together in Multiplayer.
Eat an entire family
Craft all items
Set off 20 bombs
Repair a shelter
Kill shark. Alone in Single Player or together in Multiplayer.
Eat all mushroom types
Craft 10 medicine items
Kill all animal types and display heads
Grow all plant types
Collect all robot pieces
Knock down 6 or more trees with 1 explosive. Alone in Single Player or together in Multiplayer.
Build a super long wall
Catch fish with a trap. Alone in Single Player or together in Multiplayer.
Collect all cassette tapes!
Use the compass
Killed downed enemy with rock
Revive 10 co-op players
In Single Player, kill 100 cannibals
Kill bird with arrow
Make and wear stealth armour
Chop up 50 bodies
Share a food or drink item in MP
Share a weapon in MP
Cut down 100 trees
Sleep on yacht
Survive 5 nights
Revive one co-op player
Kill a bunny. Alone in Single Player or together in Multiplayer.
Survive 1 night
Eat an enemy
Sleep with another player (group sleep)