It is also mentioned here that in addition to weight loss, you also need to refer to the fat rate. If a person's fat rate is low, there is no need to lose weight even if he is overweight. So on the other hand, if you lose weight by controlling diet and exercise, your weight may change obviously for a while, but your body fat is actually decreasing, but your colleagues' muscles are also increasing, so you will feel that your weight change is not obvious.
Generally speaking, as long as you can reasonably control your diet and increase your exercise, it will have an effect in one week, and your weight will be reduced appropriately. The appearance of 2-4 kg varies from person to person.
I hope you lose weight successfully.