>>290561596
If you click through the Armature in the hierarchy to Hips -> Spine -> Neck -> Head you can rotate the head around.

>>290561829
The "Body" gameobject underneath the avatar root in the hierarchy is usually just the entire skinnedmesh, head and all. Some models have multiple skinned meshes for different parts though, which is bad for performance and you should join the meshes in blender eventually.