I'm not too sure. When I first encountered LLMs, I decided to try implementing one from scratch. I didn't get far, because it's difficult, and I only have finite time and energy. Still, it was the process of trying to implement some basic stuff that gave me an idea of how they work under the hood.

There are videos on youtube where you can see how the token generation happens like an algorithm

The process itself is quite simple. I think everybody is surprised how well it works because it's the power of statistics + great data

Unfortunately, it can't reason at all and would need other AI fields in order to be able to tackle some other simple puzzles

3Blue1Brown has a fantastic video on GPT that I'd highly recommend called "But what is a GPT? Visual intro to transformers" [1]. You'll need to have some background in mathematical reasoning, but not too much. He does a great job of drawing pictures to show the mathematical transformations that happen under the hood.

[1] https://www.youtube.com/watch?v=wjZofJX0v4M