my character is getting into trees, trees are not colliding with character
1/ Be sure that you have a collider on your tree and your Character.
2/ Be sure that both colliders are not set on Trigger.
3/ Check the Edit/Project Settings/Physics → Layer Collision Matrix and if Trees have a tag that collide with the Character’s tag.
The documentation page:
talks about tree and colliders. If this isn’t working for you please provide more details.
(and I closed your duplicate thread. Please don’t post the same issue multiple times.)