Do you think a restaurant run by teenagers would be successful? You don’t have to speculate. McDonald’s is run almost entirely by teenagers, as is every other fast food outlet in Australia. My daughter is one of those people who work in a customer facing role.
The Gap Year usually follows secondary school year 12 graduation or is a break in the first few years of University. The challenge this presents is that you have to look for relatively low-skilled jobs in industries that are not looking for long-term employees as a criterion for employment. A paid gap year is possible.