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