Courses, books, etc.
Eloquent JavaScript
Structure and Interpretation of Computer Programs
Dive into systems
Writing a Vistual Machine
Beej guides - either on network programming or C
Stanford C engineering lectures
Random links
https://craftinginterpreters.com/
https://c9x.me/compile/bib/
https://cpu.land/
https://research.swtch.com/gomm
go garbage collection