I’ll move your post to the Getting Started forum.
In the end, a tutorial pretty much tells you what to type so you simply need to compare your code with what the tutorial is doing so it seems you’ve missed a step and/or have typos.
To “help” you requires someone following the above tutorial and comparing what you’ve typed; something that you should be able to do yourself.
Note that the best way to post script is to use code-tags otherwise devs have to download source files for your post and most are reluctant to do that.