Here is the full list of all 50 Wolfenstein: The New Order achievements. It takes around 20-25 hours to unlock all of the achievements on Windows.
Complete game on I AM DEATH INCARNATE! (or ÜBER)
Complete game on ÜBER
Unlock demolition perk 7
Unlock demolition perk 5
Unlock demolition perk 6
Unlock demolition perk 4
Unlock assault perk 7
Unlock tactical perk 7
Unlock assault perk 3
Unlock assault perk 5
Unlock tactical perk 6
Unlock assault perk 6
Solve the fourth Enigma code
Solve the third Enigma code
Solve the second Enigma code
Solve the first Enigma code
Complete game on any difficulty
Collect all gold items
Release friend
Unlock assault perk 8
Collect all letters
Unlock demolition perk 8
Defeat the London Monitor
Unlock tactical perk 8
Unlock demolition perk 3
Unlock assault perk 2
Unlock tactical perk 5
Locate the underwater stash
Unlock demolition perk 2
Unlock tactical perk 4
Collect 25 gold items
Unlock stealth perk 8
Unlock assault perk 4
Unlock stealth perk 4
Unlock stealth perk 6
Unlock stealth perk 3
Unlock stealth perk 7
Choose to save Fergus
Unlock assault perk 1
Unlock stealth perk 5
Find the Laserkraftwerk
Unlock tactical perk 3
Unlock tactical perk 2
Locate the resistance
Unlock stealth perk 2
Unlock tactical perk 1
Choose to save Wyatt
Unlock stealth perk 1
Unlock demolition perk 1
Save allied planes