Here is the full list of all 50 Wolfenstein: The Old Blood achievements. It takes around 15-20 hours to unlock all of the achievements on Windows.
Complete game on any difficulty
Complete game on I AM DEATH INCARNATE! (or ÜBER)
Complete game on ÜBER
Unlock the Grenade belt perk
Choose to save Kessler
Collect 32 gold items
Complete the nightmare in chapter 6
Unlock the Reload mash perk
Unlock the Kampfpistole ammo storage upgrade perk
Unlock the Schockhammer clip upgrade perk
Unlock the Tough Skin perk
Collect 5 letters
Complete the nightmare in chapter 5
Complete part one
Complete the nightmare in chapter 4
Unlock the Bombenschuss clip upgrade perk
Unlock the Armor upgrade II perk
Unlock the Armor upgrade I perk
Escape Castle Wolfenstein
Unlock the Vampire perk
Unlock the Quick turn perk
Unlock the Ammunition upgrade perk
Collect 16 gold items
Collect 8 gold items
Unlock the Health upgrade III perk
Unlock the Health upgrade II perk
Unlock the Health upgrade I perk
Infiltrate Castle Wolfenstein
Choose to save Annette
Complete all nightmare levels
Complete the prologue nightmare
Complete the nightmare in chapter 1
Complete the nightmare in chapter 2
Complete the nightmare in chapter 3
Complete the nightmare in chapter 7
Complete the nightmare boss level
Achieve gold medal for this challenge map
Collect all letters
Collect 64 gold items
Unlock the Eagle Eye perk
Unlock the Carry heavy machinegun perk