I figured the way to learn about computers was to build one. I used the instruction set of a PDP-8 since its paper-tape software was freely available. To this day I have not seen the electrical nor detailed logical diagram of a PDP-8. My machine, which occupied much of a six-foot rack, started running in 1970. It was terribly slow, ten microsecond cycle time, and used a core memory surplus from an old IBM machine - all 4K 12-bit words. I used a teletype ASR-33 for IO. FOCAL was an interactive language (for the PDP-8) which ran on my machine. I also wrote a few useful programs in assembler.
I had already taken an introductory Fortran course.
From there I progressed to a Northstar Z-80 based machine, which still sits in a corner. I shuddered when I recently found its bill-of-sale US$2400.
Computers are now so complex, where do people start these days if they are hardware oriented?
Later I built a local area network including the hardware ... from the chip level ... using a 6502 microprocessor in each node. It went into service in 1979 and grew to over 1200 nodes before being replaced by an Ethernet.
I not only feel old, I am old.