Is it possible to add new objects that you spawn in the editor with an editor script or something? If so, how would I code it? I mainly want to know because I am making some generic prefabs that would be really nice to quickly spawn via this right click menu.
You can use attributes in your C# scripts:
[CreateAssetMenu(fileName = "New Scriptable Object", menuName = "Create My Scriptable Object")]
public class MySO : ScriptableObject
{
}
or
[ContextMenuItem("Do something", "SomeFunction")]
private void SomeFunction()
{
}
You can check out more C# attributes in the Unity script reference: