Test blood sugar before meal and 1 to 2 hours after the meal.
Type-2 diabetes is more common in adults. But with increasing obesity rates and less physical activities among children, the rates of type-2 diabetes among children are also increasing. Thus, yes children can also have type-2 diabetes. But symptoms of it appear very slowly.
With a lifestyle change and proper diet you can manage blood glucose levels even without medication. But taking medicines or not taking them is to be decided based on your condition by the doctor.