Your weight loss depends on how many calories you have been eating per day, how many calories you intend to reduce and how much exercise you get. (Assuming you have no disease or metabolic disorders that would affect your weight loss.)
Your letter sounds like this is not your first attempt at losing weight. Perhaps your short-term efforts have not been successful because you have not changed your fat eating habits for healthy eating habits. While a meat and vegetable diet (high protein and low carbohydrate) may produce quick weight loss results, you cannot eat like that forever.
A high protein, low carbohydrate diet is a dehydration diet. Most diets caution you to drink 8 cups of water per day which is to remove waste products like ketones created by this diet. What are you going to eat when you go off your weight loss diet? Are you going back to your fat eating habits? Instead, a diet containing My Plate of meat, dairy, bread, fruits, vegetables, and healthy oils is more successful in the long run. If you ate smaller portions of bread and potatoes as well as smaller portions of meat and vegetables spread out over 3 meals per day, you would consistently lose weight. When you get to your weight goal, you can still follow the My Plate eating plan by increasing the portions slightly and you should be able to maintain your slimmer self.
If you would like a personalized healthy eating plan, try my HELP Healthy Eating For Life Plan®. HELP will consider your food preferences for type of milk, meat or not, beans or not and snacks or not. A small food database is linked from your plan from which you can create menus.
Aim for a 1 to 2-pound weight loss per week. At this rate, it will take you 15 to 30 weeks to lose 30 pounds.