Earlier quoted context omitted.
It would take him 5-10 years to become a competent programmer. Does he want to finally achieve stability in his career at age 70? I would suggest that he become a business advisor to small companies. His expertise is invaluable and he could be useful immediately.
I disagree that it would necessarily take that long. Per the OP, his father is not starting from scratch, and has some programming in his background. Being a CEO, CCO, etc... We can assume his father is an intelligent and successful person. Possibly, if his father applied himself, he could find himself a niche in which he would be adequately competent within 2 years. To include being a freelancer or independent devel…
> Being a CEO, CCO, etc... We can assume his father is an intelligent and successful person.
Being unable to continue working as a CEO/CCO suggests he's not currently very successful, and to put it lightly, CEO "intelligence" (whatever that means) doesn't necessarily translate to the kind of intelligence necessary for software engineering