[Fordec]

Most major chipsets have their design specs in PDF format online with all the info there for interfacing on a hardware level. Many drivers these days are open source. Kicad is free to use for designing PCBs.

And finally https://www.youtube.com/@PhilsLab has some good tutorials.

Finally, goo into things with an attention to detail to polish a board. A hobby board takes far less time than a product board, but all it is is time and thinking about each attribute more. You don't need third level education to have that work ethic.

Best of luck!