I've never really considered myself to be a programmer. I dabble very badly in Python but I've always been confused by what goes on at the CPU level.
Assembler & Machine Code seem to be where you get to grips with what's really happening.
I'm going to build a small 6502-based computer, with the bare minimum of hardware & features…. CPU, ROM, RAM, I/O and some form of display.
I was going to source the parts myself, but found it impossible to find a supplier with stock of the usual 28C256 EEPROM. I've been watching the excellent You Tube video series by Ben Eater:
https://youtube.com/playlist?list=PLowKtXNTBypFbtuVMUVXNR0z1mu7dp7eH
Ben supplies a kit with everything needed to build the basic computer - just add a PSU and an EEPROM programmer - so I've bought one of his kits.
I've ordered a TL866 programmer from Amazon as well as a well-regarded book Programming the 65816: Including the 6502, 65C02, and 65802