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.
Choose to save Fergus
Unlock demolition perk 5
Complete game on any difficulty
Complete game on I AM DEATH INCARNATE! (or ÜBER)
Complete game on ÜBER
Solve the fourth Enigma code
Collect all gold items
Release friend
Collect all letters
Defeat the London Monitor
Solve the third Enigma code
Unlock demolition perk 8
Unlock tactical perk 7
Locate the underwater stash
Unlock tactical perk 5
Unlock assault perk 7
Unlock demolition perk 4
Solve the second Enigma code
Unlock assault perk 8
Unlock tactical perk 6
Unlock assault perk 6
Collect 25 gold items
Unlock stealth perk 4
Solve the first Enigma code
Unlock demolition perk 3
Unlock tactical perk 8
Find the Laserkraftwerk
Unlock assault perk 5
Unlock assault perk 4
Unlock demolition perk 7
Unlock demolition perk 6
Unlock tactical perk 4
Unlock demolition perk 2
Unlock assault perk 3
Locate the resistance
Unlock stealth perk 8
Unlock stealth perk 6
Unlock tactical perk 3
Unlock stealth perk 3
Unlock stealth perk 5
Unlock stealth perk 7
Choose to save Wyatt
Unlock assault perk 2
Unlock tactical perk 2
Unlock demolition perk 1
Unlock assault perk 1
Unlock tactical perk 1
Unlock stealth perk 2
Unlock stealth perk 1
Save allied planes