If you are talking about alcohol, a 16 or 17 year old can drink beer wine or cider with a table meal (more than a sandwich) if both are bought by an adult. The adult does not have to be a parent but must be 18 or over.. The adult must be present when the meal and drink are being consumed by the child. It must be eaten at a table or a counter provided this is not used for serving refreshments.
Although this is allowed is it up to the discretion of the restaurant? Recently on a weekend break to Center Parcs they refused to allow me to purchase a glass of wine for my 17 year old daughter even though we were eating a meal.The manager explained it was against their policy .