Ben Eater’s 8 bit breadboard computer project on YT is well explained, and he sells the kits. I forget Ben’s credentials, but he is a professor in CS somewhere. His teaching skill is remarkable.

Some poor sap made a more intuitive set of schematics that also breaks down the kits: github.com/…/8-Bit-Breadboard-Computer

That same guy made some chip labels that some people find useful: github.com/Upcycle-Electronics/ChipLabels

That last one also has a link to a list of databooks on archive dot org. Get the 1996 Motorola CMOS logic databook as your primary starting point reference. That goes into a lot of the details about cross compatibility and exactly what works and what doesn’t.