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
Complete the nightmare boss level
Complete the nightmare in chapter 7
Choose to save Annette
Unlock the Kampfpistole ammo storage upgrade perk
Complete the nightmare in chapter 6
Unlock the Quick turn perk
Unlock the Tough Skin perk
Unlock the Grenade belt perk
Collect 32 gold items
Collect 5 letters
Complete the nightmare in chapter 5
Complete part one
Unlock the Health upgrade III perk
Unlock the Health upgrade II perk
Complete the nightmare in chapter 4
Escape Castle Wolfenstein
Unlock the Eagle Eye perk
Unlock the Ammunition upgrade perk
Unlock the Armor upgrade I perk
Unlock the Schockhammer clip upgrade perk
Unlock the Bombenschuss clip upgrade perk
Collect 16 gold items
Unlock the Vampire perk
Unlock the Reload mash perk
Collect 8 gold items
Complete the nightmare in chapter 1
Unlock the Health upgrade I perk
Infiltrate Castle Wolfenstein
Choose to save Kessler
Complete all nightmare levels
Complete the prologue nightmare
Complete the nightmare in chapter 2
Complete the nightmare in chapter 3
Achieve gold medal for this challenge map
Collect all letters
Collect 64 gold items
Unlock the Armor upgrade II perk
Unlock the Carry heavy machinegun perk