Great : from your literature, Vercel's FaaS is basically AWS Lambda with plumbing.
Since Netlify appears to be a smaller player (40% of your revenue) and since they similarly don't talk about their stack much, I'm going to presume that they're doing the same thing hehe
Don't start in the obvious places, because you can get stuck there for a decade before figuring out what else is going on ( I did, you shouldn't ) ( quick dive ; quick dip )
1. do a quick read on how UNIX and Linux kernels were designed, particularly what "file handlers" and "sockets" are ( day 1 ; 30 minutes )
2. do a quick read on the difference between "command prompts" (1-dimensional) and "pseudo-teletype terminals" (2-dimensional) ( day 2 ; 15 minutes ) ... note that both are varieties of "shell" ; shells are opposed to kernels
3. do a quick read on what "display managers vs window managers" are ... and if possible ( now this is quite hard, as the docs are messy ) ... how the kernel, talks to the shell, which talks to a pseudo-teletype terminal, which is a display client to the display server, which talks to the display server, which talks to the window manager ( it may not be exactly like that, but this is a good assumption to make until you get a clearer view ) ( day 3 ; 2 hours )
4. then learn a shell scripting language
5. then do something like "espeak 'oh hi there'"
Alternatively, do this in reverse numerical order.
Yeah - I don't know how to evaluate this, but I'll stan it until someone who does know can give a proper opinion :)