I went through Turing Complete up to a working CPU and found it incredibly fun. I then went on to build my own RV32I (simplest RISC-V instruction set) core in Verilog - if you keep a simple single-cycle design, it doesn’t end up being super complicated and not a ton of code. I’d recommend the exercise for anyone wanting to learn about how CPUs work.

Also, for people interested in this type of thing, look up Ben Eater’s 6502 videos. Wiring up a 6502 (old microprocessor) to ROM and RAM on a breadboard; later he builds a “world’s worst video card” - more like a VGA display output card, still pretty cool.