Here is the full list of all 38 Dark Souls II achievements. It takes around 60-80 hours to unlock all of the achievements on Windows.
Max-out devotion to covenant
Inherit Benhart of Jugo's equipment
Inherit equipment from Lucatiel of Mirrah
Light all flames on the map in Majula
Defeat Vendrick
Inherit Captain Drummond's equipment
See the ending
Discover an ancient covenant
Discover the abysmal covenant
Learn all gestures
Acquire Ashen Mist Heart
Inherit Steady Hand McDuff's equipment
Acquire the King's Ring
Defeat Looking Glass Knight
Inherit equipment from the head of Vengarl
Light the primal bonfire in Brightstone Cove Tseldora
Inherit Laddersmith Gilligan's equipment
Reinforce a weapon to its limit
Discover the covenant of the fittest
Discover the covenant of rodents
Light the primal bonfire in the Iron Keep
Light the primal bonfire in the Black Gulch
Increase the population of Majula
Give Rosabeth of Melfia something to wear
Discover the covenant of the protectors
Discover the clangorous covenant
Discover a most brilliant covenant
Discover the covenant of the bloodthirsty
Light the primal bonfire in Sinner's Rise
Discover the covenant of the meek
Defeat the Last Giant
Die for the first time
Reclaim flesh and set out as an Undead
Earn all achievements
Learn all sorceries
Learn all miracles
Learn all pyromancies
Learn all hexes