Please check out the
spine-unity Runtime Documentation: BoneFollower
In general we recommend to always have a look at the spine-unity documentation page first, as it covers many common tasks and problems:
spine-unity Runtime Documentation
If any time you want to use visual scripting, you still need to follow the programming documentation sections, because visual scripting basically just turns every "word" of code into a Node (just without assigning variables for easier reading).
Bone bone = skeletonAnimation.Skeleton.FindBone("boneName");
Vector3 worldPosition = bone.GetWorldPosition(skeletonAnimation.transform);
would result in