I’d recommend you watch video tutorials on KiCad to get started with making a board. I’d recommend starting a little simpler - by making a custom board on a b

I’d recommend you watch video tutorials on KiCad to get started with making a board. I’d recommend starting a little simpler - by making a custom board on a breadboard using pin breakout PCBs - https://www.adafruit.com/product/1377 https://www.adafruit.com/product/1377 That will give you an idea about the bare minimum circuit one needs to build a functioning board (crystal, power regulator, boot select buttons, and so on)