I understand that it's probably 2 separate questions - about the engine and about graphics. And that's graphics maybe really difficult topic, which only people with really good engineering mind can understand and there's no easy way about it, and it is not worth to study until I really want to be specialist in this and spend several years in studying. I mean, I'm ready for that answer, just want to be sure.
Yes, I know about that article, and it seems like good resource for understanding engine, though I feel like it's not exactly starting point for newbies, but more of a review of the Quake engine code for those, who already understand basic principles of how game engines works. But I could be wrong.
I thought maybe there are a series of old articles/tutorials exist somewhere, or some good book that could clarify this more elaborately.
Also, speaking of graphics, I found some video course about modern OpenGL (not sure if I should leave external links here), and begging of it seems pretty comprehensible for newbie like me, though I'm not really sure about "modern" part. But, maybe after finishing it, it would be easier to understand "older" versions used in Quake.
And also on this side (fabiensanglard) I read about the book "Computer Graphics: Principles and Practice in C", but based on Amazon comments it's also not a beginners level material.
The quake engine is not "beginner material".
You should start off with learning about game programming in a more general way using libraries such as SDL2 (in fact I think QuakeSpasm uses SDL2)
First hit on googling "SDL2 tutorial":
Seems to start at the "hello world" level.
Ok, thank you for advice. I presumed there's no easy way, but needed to be sure.