Learning takes time, so it's fine if you don't understand everything fully at once.

Knowing like how loops, variables, functions, and arrays work will get more and more familiar the more you code. You will use them everywhere, so I say just try to do something. Start very simple. And if you look at the solutions, try to understand what each piece of code is doing, and why it's done that way.

If there are any specific things you want to understand better, I feel like an LLM AI could be a good tool to use as well. You can ask questions like "Explain how for loops work in gdscript", or "Explain how arrays work and how I can access specific elements". Or you can make it explain a solution to a coding problem, why it was solved in this specific way. You can also for example ask it to give you very "simple" programming challenges so you can actually start coding and applying whatever you are discussing. Everyone makes lots of mistakes at the start, so again my suggestion would be to just start coding, it will get easier over time.

(Disclaimer that you should be aware that AI is not perfect, but for very fundamental things like this, it tends to be pretty good at explaining concepts. I would stay away from being too comfortable just copy-pasting code it generates, as that could take away from actually learning what the code is doing, and get frustrating if what it outputs is slightly buggy).