this is a problematic question
some people think that carbs with a lot of fiber or carbs with a lot of fat or carbs with a lot of nutrients are good for you while "empty" nutrion low carbs are not.
An example of a good carb would be a vegetable, a fruit or a whole grain
And example of a not so good carb would be sweets, cakes, white pasta, white flour, white rice
Cereal can be good - you just have to make sure it is whole grains and without too much sweetener added and other junks added. Things like real oats would be best
Yogurt without added sugar would be good
Whole wheat bread - maybe - 100% whole grain bread may be better.
juice - I think eating the fruit is better as you get the fiber with it.
I did am doing Atkins so when I started I cut out all carbs except some non starchy veggies but I have gradually added some more. Of course on Atkins one does eat fat so it is a whole different kind of diet