"You must at least create a scene" error

Hello fellow developers! I am following this tutorial Codez une première arme ! - Créez votre propre FPS en WebGL - OpenClassrooms to create a FPS using Babylon.js. I have followed along in this playground https://playground.babylonjs.com/#MV055Z#7. However, there is an error message at the bottom: “You must at least create a scene”. I am actually returning a scene from the “createScene” function. Can you please give me a hand with this one? Thank you!

Hey this is because you are creating a new Engine.
The Playground is already creating one for you:

Unosquare Demo | Babylon.js Playground (babylonjs.com)