In version 1.02, many players were just starting out and looking for the "proper" tools to beat early bosses like the Chained Ogre:
Sold by the Pot Noble Harunaga in Hirata Estate for 7 Treasure Carp Scales. sekiro-shadows-die-twice-v1-02
Are you trying to find a specific item to progress past a certain boss? Sekiro: Shadows Die Twice - Walkthrough Part 1: Shinobi In version 1
If you are looking for a "piece" to complete a larger set, it's likely one of the three fragments of the Dancing Dragon Mask : Prayer Beads or Gourd Seeds Sold by Pot
Sold by the Dungeon Memorial Mob near the Abandoned Dungeon Entrance for 5,000 Sen. 2. Key Prosthetic "Pieces" (Early Game)
Used to break shields; also found in Hirata Estate inside a small shrine. 3. Prayer Beads or Gourd Seeds
Sold by Pot Noble Kormori at Fountainhead Palace for 12 Treasure Carp Scales.