Here is the full list of all 34 Sekiro: Shadows Die Twice - there are GOTY Edition achievements worth 1,000 gamerscore.
All achievements have been unlocked.
Acquired all skills
Attained the "Shura" ending
Defeated "Isshin Ashina"
Defeated all bosses
Attained the "Immortal Severance" ending
Attained the "Purification" ending
Upgraded all Prosthetic Tools to their limit
Used Lapis Lazuli to upgrade any tool to its limit
Defeated "Great Shinobi - Owl" at the Hirata Estate
Upgraded Vitality and Posture to their limit
Attained the "Return" ending
Defeated "Sword Saint Isshin Ashina"
Defeated the "Demon of Hatred"
Fully upgraded the "Healing Gourd"
Defeated the "Great Colored Carp".
Defeated the "Divine Dragon" and obtained the "Divine Dragon's Tears"
Defeated the "Corrupted Monk"
Traveled to all areas of the game
Acquired all Prosthetic Tools
Defeated "Great Shinobi - Owl"
Defeated the "Great Serpent".
Grasped the inner mysteries of any combat style
Acquired all Ninjutsu Techniques
Used the Mortal Blade to sever the Guardian Ape's undying
Caught the Folding Screen Monkeys
Defeated the "Guardian Ape"
Defeated "Genichiro Ashina"
Defeated "Lady Butterfly"
Encountered the Memorial Mob
Defeated "Gyoubu Masataka Oniwa"
Returned from the dead using "Resurrection" for the first time
Acquired the Shinobi Prosthetic
Received the "Kusabimaru" from Kuro