On this page of the Resident Evil Village guide, you will learn how to interact with the wells to trigger the mechanism and get the loot from the well. This is important if you want to get 100% of treasures.
You can find wells right from the beginning. They are located in different parts of the village, but Ethan initially cannot use them - he needs to find the right item. Nevertheless, it is worth looking around for wells to add their location on the map.
You can start collecting treasure from the wells after defeating the boss in the castle and returning to the starting village. Ethan can now explore the Workshop area shown in the pictures. Its gate is locked - use a knife or gun to destroy the padlock.
You can solve a combination puzzle in a small hut. The correct combination is 070408. In the stash, you will find, among other things, a Jack Handle.
Take it and go to the tractor shown in the picture. Use the handle on the yellow jack to lift the tractor and crawl under it.
While exploring the new part of the village, you must watch out for new Lycans, including an armored variant. The destination is the gate shown in the picture, which Ethan can now open using the Iron Insignia Key he acquired earlier.
Inside the small building, you will find the Well Wheel - this is the item you need.
You can now interact with wells - select the Work Wheel to use it. You will pull a bucket with treasure. Each well, of course, hides a different loot - these can include unique treasures or ammunition. Investigated wells are crossed out on the map, so you can easily locate those that still have loot.