1. You need to find the location of the legendary beaver, so first open the map and find the following place:
2. You can find the broken stick under the local tree.
3. Then trace the feces beside the railway
4. Then follow the track across the railway to the river and find the broken stick
5. Swim to the other side of the river and you will see white beavers (be careful not to scare them away when you get ashore)
6. Also shoot and peel the skin to get the legendary beaver skin (the legendary skin can be beaten casually)
The above is the entire guide to the location of the legendary beaver in Red Dead Redemption 2. I hope it will be helpful to you.