Go to "scene" in the right panel of the editor, rightclick on World and click on "Load All". Your stuff needs to be loaded everytime you open the editor.
Ps: Questions like that are answered in Klabautermanns video tutorials for beginners. You'll find them in this forum.
thanks so much! also I am not finding a video showing how to Play the game inside the editor. I need to Hop in and Out to make sure I am scaling everything properly in my world.