Whenever the TI 99/4a dropped in price. That was when I started. So almost 40 years. I find the key was not being given everything and being forced to do things on your own. My son is smarter than me and could code at 5 but he's happy to use steam and chat and is only passing interested in computer--mostly when his machine won't run windows or Linux correctly so he can run his vidya and discord. He became interested in AI/ML only when I showed him it could help with D&D