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