Yes cornflakes are good for breakfast.
Cornflakes while not very nutritious do make for a fulfilling breakfast and they are pretty healthy.
The cornflakes do provide your body with some whole grains and fiber content which helps keep your body healthy and eating cornflakes for breakfast can also give you some needed energy to start your day.
If you want more nutrition and vitamins you should also add some fruit to the bowl of cornflakes.
I like to add some apples slices or even strawberries, blueberries etc to my bowl of cornflakes when I eat them in the morning.
I sometimes like to eat a bowl of cornflakes before bed as well.
Even adding banana slices to the cornflakes is a good thing as the bananas also provide you with health benefits and make the cornflakes more fulfilling and even gives you more energy.