Is this a good plan?

I am going to just eat 3 meals a day with a healthy fruit snack. and im gonna walk 3 miles a day for 3 to 4 months. And play video games LESS! Like once a month or neva! ANd these are the list of what im only gonna eat. For breakfast im only gonna eat, Cereal (Fruity Pebbles),or fruit, or vegetables. For lunch im only gonna eat, Fruit, or nutrigain bar, or mac & cheese,or vegetables. For Dinner im gonna eat,or chili,or spaghetti,or ribs,or mashed potatoes, or peas,or corn, or carrots. Is that a good plan?