How to Get Charm of Soaring Focus | Ghost of Yotei

Earn infinite Concentration when aiming a bow or rifle while jumping.

You need to liberate Yōtei's Shadow Inn twice. One from the main quest. And the other, by doing the following:
・Make sure you remove Atsu's bounty poster on the bounty board and that you already defeated another member of the Yōtei Six besides Snake.
・Come back to the inn and Saito's Black Guards will be there.
・Defeat the guards.
・Ran will insist on giving you the charm as a reward.