Nice presentation!
Learning a powerful software like AmiBroker is not the most straightforward task, but some resources will significantly help you.
First of all, the official documentation, the manual, the help file (pressing F1 on the code editor will bring you to the relevant section of it).
In particular, as a first step, @Tomasz recommends studying the tutorial.
It is also handy to have a browser bookmark to the Function Reference - Categorized list of functions.
Another great resource is the Knowledge Base. When I began my journey with AmiBroker, I spent a fair amount of time reading ALL the KB Articles (testing the code, where provided, to understand it better).
Also instrumental to my learning process (that never ends) is this excellent Community Forum.
I suggest spending a lot of time reading the past threads. Experiment with the "Search" functionality extensively; your question/difficulties probably are the same that other users already encountered and were solved by some of the more experienced users.
When you notice a response from someone you particularly like, go to their profile and check out the past activity and solutions they provided - this is a shortcut to focus on the most useful threads.
Do not forget to bookmark the topics that you'll think are relevant to your trading style to come back when required (or even better save the code to your Snippets collection).
Learn how to debug your code, but when you are lost - it happens to (almost) all of us - feel free to ask for help. Be sure to follow the main forum guidelines:
Happy learning and again... Benvenuto / Hartelijk welkom!