I'm trying to create a door that rotates realistically (like opening and closing) in Unity 3D, but I'm encountering some issues:
What I've Tried
Although the image is a bit dim, I noticed the button on the top left of the scene window, you selected Center, you need to select Pivot.
Also you can check the section "Gizmo handle position toggles" in the document: https://docs.unity3d.com/Manual/PositioningGameObjects.html