SuperGibaLogan (i wrote these lines of code exactly how the tutorial shows how)
Again, you didn't. You made errors when re-typing the tutorial code.
You need to learn the basics of GDScript syntax so you can understand what you're actually typing. It's pointless to mindlessly copy the code without understanding it, and as you can see, it's very easy to unwittingly produce a bunch of typos. I'd suggest to do a more basic tutorial than this one. Preferably the introductory 2d tutorial in the engine docs. Go slow and focus on what is being shown. Details matter a lot when coding. One mistyped character can break your entire script.
Luckily the engine tells you about it. An error message will always be shown when there is an error in a script. Aim to understand what a particular error message means. It's your hint about what you did wrong.
In the code you posted above, you have at least one syntax error; missing colon after typed function argument next_position