Question Can't use a namespace in a script from the FPS Micro-Game

Hi everyone!
So i created and imported a package from another project to the FPS micro-game. I tried to call the namespace of the package from a script from the microgame, but it didn't catch the difference. To test i created another c# class and put it outside the folder, and there i could call the namespace, but if a move it to folder i could not.




In red is where i located the scripts from the package. In blue, is the folder with the scripts i'm tring to modify, to which i need to use the "MovingHud" namespace but i can't. And in green is the test class where i tried to call the namespace succesfully.

What can i do to use the MovingHud scripts from the Gameplay folder??
And by the way, what does the cubes on those folders mean??