Autohotkey itself is coded in C++ and does a lot of stuff with the Windows API (imagine rather cryptic dll calls and stuff), which is much more complicated than AHK itself.
Imho you are doing the right thing - looking at forum posts. Then, try to play around with the code snippets, look things up in the docs that you don't understand and ask questions, if that doesn't help. Also, try all the examples from the docs and try to change and combine them.
Of course, you can also find many basic concepts in AHK that you could look up elsewhere, for example regular expressions. Another example, objects in AHK are (more or less) similar to object-oriented concepts in other programming languages. So, you could look at general texts about object-oriented programming if you wanted to get a deeper understanding of it. There are videos on Youtube about all kind of general programming topics, including videos about AHK.
Forum member Joe Glines has made a series of very good Youtube videos about webscraping and data handling, if you are interested in these topics.
In the end, there is no magic button to press. I personally did my first programming in the 1980's on Sinclair Spectrum and Amstrad home computers - in the 90's I did a lot of Visual Basic for Applications, a bit later I did some programming with SQL, Java and statistical programming packages - and some other things that I already forgot. That's why I have a certain knowledge about some basic concepts of programming - but I still don't know much compared to others here. One reason is that everyone has another learning curve, of course also based on specific use cases, experiences in the past and different amounts of enthusiasm and time that can be spent. For some people, thinking in algorithms comes natural, for others not so much... often, it can help to plan a complex series of actions in pseudo-code, before you actually program it.
I think you learn the most by actually doing something. Write some code and then review how it can be improved or find out, why it is not working. This can be frustrating at times - but that is part of the learning process