After some reading today, there isn’t much info on how cells form into specific shapes for arms, hands, organs, etc. (I am sure there is a ton of data, but I don’t know what subject to Google.)
Perhaps the term you’re looking for is morphogenesis.
Yes, thank you. That is exactly what I am looking for. I dunno what I expected, but I was hoping that I was going to avoid a ton of maths. Alas, everything seems to be math. /s
For those who are interested, this led me directly to these: