At this time of year, a lot of people resolve that they are going to try to lose weight. Its important that you try to set sensible weight loss goals,because if you try to aim too high, you will get demoralized with your lack of progress, or end up using unsustainable techniques for your weight loss.
A good goal for someone with a lot of weight to lose is 8 pounds in two weeks but if you are not classed as obese on the BMI scale then this is a very high goal, and you are unlikely to achieve it. People who are merely overweight should aim lower 2-4lbs in two weeks, instead. Yes, BMI is not a perfect indicator,but unless you are a professional bodybuilder it will most likely be fairly accurate for you.
Weight loss, in its purest form, is about calories in vs calories out. Different diets, such as keto, intermittent fasting and weight watchers all just make it easier to stick to creating a calorie deficit.
To lose 1lb of your body fat, you need to live in a calorie deficit of 3,500 over a given period of time. Most diets advocate that you eat 500 calories fewer per day than you would normally need for your average activity level, which means weight loss at a rate of 1lb per week. You can speed this up by exercising, to burn more calories.
When you clean up your diet, you will find that over the next couple of weeks you lose weight rapidly but not all of the weight is fat. A lot of it is from water retention. You may even shed some weight simply from increasing the amount of fiber in your diet too.
This initial weight loss will stall quite quickly but that doesnt mean that you should give up. Keep logging the amount of food that you are eating, and weigh and measure your food too.
Weigh yourself once a week, on the same day of the week and at the same time of day (ideally first thing in the morning after using the toilet).
If, after a few weeks of sticking to your calorie goals your weight loss has still stalled, cut your calories by another 200 or so, or, alternatively, exercise more, so that your weight loss starts again.