Breakfast- eggs, bacon, cheese, anything non carb really. Full fat sugar free yogurt with a few berries. Coffee with cream (not milk) or tea, no sugar but a bit of sweetener is fine. Personally my caffeine choice is diet coke. No juice of any kind and no milk, both are full of sugar, even the unsweetened kind.
Lunch- salad with full fat low carb dressing. Can add lots of things to it such as chicken, ham, bacon, hard boiled eggs, cheese, avocados, almonds, olives. Or a plate with assorted finger foods like devilled or boiled eggs, cheese, veggies and dip (check carbs in dip) pepperoni, etc
Dinner- meat of some kind or chicken or fish with steamed veggies and lots of butter. Or a stir fry without rice or noodles. I use wilted mung bean sprouts instead of noodles or you can use courgettes spiralized or spaghetti squash. Cauliflower can be used to make tasty faux rice or mashed with butter and cheese or garlic like potatoes.
Snacks can be a few nuts or 85% dark chocolate. Sugar free jelly with double cream or berries in cream or full fat sugar free yogurt. Pork scratchings, jerky.
No milk and no juice. Use cream for coffee and your pepsi max is fine. Use full fat products. Low fat products have been filled in with sugars and chemicals to make them taste like food and you need the fat to feel full. No fruit other than berries and maybe apples and pears but you will need to check with your meter if you can tolerate them. You do have a meter right??? If not you need one. How can you know how foods affect you if you don't test?
If you check out low carb recipes on the forum or on line you can find thousands of tasty meals. There are also lots of threads on here along the lines of "What did you eat for breakfast" Look in the low carb diet subforum.
This is how I do it. Not everyone follows a diet this low in carbs. You will need to use your meter to see what you personally can handle in the way of carbs. This is just a rough idea of where to start. The atkins website is also a good starting point with lists of foods and a clear explanation of how to do it. Just don't buy any of their fake foods.
I am not a doctor or a nutritionist and I am not giving you medical advice but I hope this helps.