One of more frequently recommended books is Jason Gregory’s ‘Game Engine Architecture’. Neither version I have is too deep in code specifics, but for standard A

One of more frequently recommended books is Jason Gregory’s ‘Game Engine Architecture’. Neither version I have is too deep in code specifics, but for standard AAA game development (Gregory was/is at Naughty Dog on their engine team) it is a pretty detailed look at the structure and options of game engines. For a more code centric resource I would say you could check out the YouTube videos by The Cherno (former EA engine dev).