A typical bagged lunch includes a sandwich, fruit and a cookie or muffin. Many students like to prepare their own lunches. If you wish to do this, suggest it to your host parents. They will appreciate your help. This is usually the largest and most formal meal of the day.
Many people have soup or salad before the main course.
Dessert, such as ice cream, is often served after the main meal. Canadian meals are often informal. You should tell your hosts if you are hungry. If you do not accept something to eat the first time it is offered, your host might assume you do not want anything. Your hosts will not know what food you like unless you tell them.