Is Corn Flakes good for weight gains?

Here are my diets: Breakfast 250g Cornflakes with 500ml soymilk (mixed with dark chocolate)

Lunch

250g Cornflakes with 500ml soymilk (mixed with dark chocolate)

Dinner

250g Cornflakes with 500ml soymilk (mixed with dark chocolate)

Is Corn Flakes good for weight gains?
Post Opinion