My 8 year old eats at mealtimes what I make for him, which is what I feed the rest of the family. I'd call him an average eater, sometimes not much and sometimes more, but never a big eater.
Breakfasts vary, but I try to give a complex carb, a protein, someting with calcium, and something with fibre. Today it was rye bread with cream cheese and smoked salmon, half a pear, a glass of milk. Yesterday it was a baked apple with Greek yoghurt and granola topping. Monday it was baked porridge with pear.
He has school lunches.
Dinner also are varied - I try to stick to 2 days meat, 2 days fish, 2 days veggie, and one day anything goes. Home cooked with minimally processed foods and stick to complex carbs. His preferences are pasta, pizzza, sushi, fish, and, not kidding, calves liver. Dislikes slimy textured foods (cooked spinach and most mushrooms). Puddings are usually saved for weekends, but the option of fruit is always available. I love to bake so there is always something on the weekends - chocolate fondants, pies, cakes, tarts. Only water to drink during the week with meals and more lenient when out or special occasions.
I don't give snacks for a regular school day, but throw in a fruity oatbar or a pack of coconut if he has a club. For home snacks, I have jars of nuts, a fruit bowl, packs of dried seaweed, crackers, and occasionally biscuits which they can access when they want, except if it is right before a meal.
A glass of milk with the more than occasional small biscuit before bed.
He is thinner than average, taller than average, and fairly active (walk to school and swims 3 times a week).