Project Prefabs

Why cant I drag and drop a gameobject from the hierarchy to a prefabs script that has a transform variable in the project folder? I hope that makes sense… lol Thanks

No this is not possible. You need to make your hierarchy object into a prefab first, then use that prefab in your other prefab inspector. Anything in the Hierarchy window only exists in that scene, so you cannot cross-reference something from the Hierarchy to another prefab in your Project window. If you were dragging from the hierarchy to the instance of your prefab in the same hierarchy window, then that would be fine as it is just for that scene.

Bottom line is no, not possible. Make your object a prefab, then use that in your other prefab.