Look, I'm not concerned about the 16-year-old. I think most 16-year-olds can speak English or French. I think if they don't, they will learn it at school. They will learn it from their friends. They will take lessons sometimes provided by the government for language.
I think the number of 16-year-olds who don't learn to speak good English or French is limited. The case at the older end of the age spectrum may be more serious. It would be very unusual for a young person not to learn English or French, I would say.