I always upvote Ben Eater's project(s).

I got his 6502 kit and worked through his YouTube videos to get it up and running with LCD display and all. I want to actually frame it and get it running, hanging on a wall.

If anyone is new to Ben, find a comfortable chair or couch, make some tea, take a breath, and begin your descent into his long-form breadboard series of nerd-splaining how a CPU works, beginning with basic logic gates.

His follow-on series is a little higher level. He's still at it with the breadboards but he allows that this time the CPU (a 6502) is already built for us. He then walks through how the address bus works, how to attach RAM, etc.

It makes me wish I could be transported back to the 70's when things could still be understood.

+1 for the 6502 kit. It’s the perfect project. I think the full 8-bit computer is kind of daunting. The 6502 is just big enough to be a fun medium size project. Plus there is a perfect extension project with the video card if you want to add that on.

His series on building a video adaptor is a particular favourite of mine.

I also did the 6502 and added a Pi Pico for VGA output and USB input.

I'm still working on ways to add more to the design -- it's been a fun hobby. I actually enjoy cutting the wires and physically putting it together.