If learning this type of low-level CS is interesting, I can't recommend the NAND to Tetris course highly enough (https://www.coursera.org/learn/build-a-computer

If learning this type of low-level CS is interesting, I can't recommend the NAND to Tetris course highly enough (https://www.coursera.org/learn/build-a-computer https://www.coursera.org/learn/build-a-computer). You start with a NAND gate (NOT AND) and built the simple gates, multiplexers, ALU, machine language, VM, compiler for a high level lang, OS, graphics engine, culminating with a game you design that runs on this computer. There's also a book with the same contents (https://www.nand2tetris.org/book https://www.nand2tetris.org/book).