Hi Bigo, and welcome!
I have a 2-egg omelette for breakfast almost every day - doesn't take long to cook, and fills me up nicely for the morning. Sometimes with mushrooms or cheese, or a bit of bacon or a sausage, but mostly plain. The few times I have cereal, I use 'Lizi's Granola' (available from most supermarkets), usually about 30g or 40g which doesn't make me spike too much. I have even been known to have cold chicken salad for breakfast - really clean and refreshing! Occasionally I'll have Greek yoghurt with blueberries.
For lunches on site, I take cold meats or cold sausages (high meat content ones have very few carbs) with some cheese, and bite-sized veg eg baby tomatoes, strips of pepper, radishes and cucumber. Sometimes I'll take a tin of tuna mixed with mayonnaise, or cubes of corned beef. A handful of nuts is nice too. With all of these you can pack them in a plastic box the night before and put them in the fridge. Just remember to take them with you in the morning!
If it's really cold I'll take a wide-mouthed flask with some hot soup - either home-made or a lowish carb canned variety - to go with my salad-y lunch. Once you start thinking outside the box there are lots of options.
You'll gather from the above that I eat very low carb, but if I want something carby and crunchy I eat oatcakes (5g per biscuit) or sesame ryvita which are about the same. The beauty of low-carbing is that once you've worked out what you can eat without carbs (meat, eggs, cheese, fish etc, and low-carb veg)) you can eat pretty well as much as you like, so no need to go hungry. It's more difficult if you're vegetarian!
And if you're not low-carbing, you can eat your daily carb allowance in the evening, in the comfort of your own home!
Hope that's of some help.
Viv 8)