I don't think there's anything like gambling experience before one can start gambling, but 18 years and above is a law in most countries these days some young lads boy cut this law because of the introduction of online gambling, some of these platforms don't carry out a proper KYC for their users, you can't start asking gambler how experienced are you before you let them play, it's not a job interview.
Online gambling has increased the number of gamblers in the world. Both lads and adults gamble without identifying their age but I think experience is still needed in the online gambling though lads play online video games but playing online video games is different from gambling. If nobody shows you or teach how to gamble you can't gamble. Some lads have the experience from peer group or following friends to gambling centers. Like me at first I don't know anything about gambling so I was not having the time to gamble until a friend taught me.