There are two label sections you need to look at:
Firstly the ingredients list and secondly the nutrition information.
Ingredients List
This one is one I found online for
Fiber One Chewy Bars - Oats and Chocolate Flavour.
You need to check the list for things like sugar/dextrose/high fructose corn syrup and all the other aka's for sugar as well as for ingredients that you are not allowing yourself because of whichever phase of Atkins you are at.
So if on induction only ingredients listed on the allowed induction foods list can be on the list to make the food 'legal' for induction.
Looking at this label you can see many non-induction ingredients, so this product would not be allowed on induction even if it had no sugar in it.
Nutrition Label
This shows how many calories/fat/carbs/fibre/protein/sodium etc in 100 grams/mls and sometimes in one serving if that is different.
Labels from non-UK products might only list the numbers 'per serving', and if the serving is small (1 teaspoon perhaps) and it contains less than 0.5 carbs in that small amount they are allowed to say it has zero carbs, which can mean if you eat several servings-worth you might be eating more carbs than you think.
You need to look at the carbohydrates in the product to make sure you dont go over your daily carb limit.
Note that in UK and many other countries outside USA fibre is not counted as a carb, so we do not have to deduct fibre counts from the total carbs to get the net carb number - it has already been done in effect.
The clue to whether the fibre carbs need deducting to get net carbs is in the spelling (fibre - uk spelling : fiber - US spelling) as well as the position in the label. In US labels the fibER is listed among the Carbohydrate section of the label instead of lower down the label in its own section.
I hope this helps