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: https://github.com/Upcycle-Electronics/8-Bit-Breadboard-Computer

That same guy made some chip labels that some people find useful: https://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.

Kits are fine, but they're kind of generic. I lost interest in making LEDs blink pretty quick.

Some of the best advice I've heard is to figure what you want to build, and make that project your first learning experience.

I'd buy myself several sets of the preformed wires, a bending triangle, one of those pre-mounted sets of breadboards like the one above, and a cheap power supply like a DC310S. If you want to go really cheap, you can get the breadboard power supplies that fit right on the rail and are powered by a 9V wall wart and deliver 5+3.3V at a low amperage. I'd also grab some duPont wires.

As for components, well that really depends on if you're planning to do digital or analog projects. I'd certainly suggest a few ULN2003 chips for relay drivers, maybe a couple of ESP32 dev boards.

There are probably better options, but when I was messing with my pico the Adafruit parts pal was great! https://www.adafruit.com/product/2975

How different can they be? Genuine question lol I've never seen anything different than my uni had