Golden Kamuy is a Japanese manga series written and illustrated by Satoru Noda. The story follows Saichi Sugimoto, a veteran of the early twentieth century Russo-Japanese War, and his quest to find a huge fortune of gold of the Ainu people, helped by a young Ainu girl named Asirpa.
There is also an anime adaptation.
The manga is, as of March 2022, around 300 chapters long and the anime is three seasons long with 36 episodes total. A fourth season is happening but its release is on an unknown date.
Where can I read scanlations? Here: https://mangadex.org/title/8847f905-550d-4fe6-bcda-ac2b896789c7/golden-kamuy
Where can I watch the anime in English? Here: https://www.crunchyroll.com/golden-kamuy
Where can I buy official volumes in English? Here: https://www.viz.com/read/manga/golden-kamuy/all