To lose weight you need a calorie deficit of 500 kcal. So you can lose about 0.5 kg of body weight per week - ideally, of course, body fat.
A calorie deficit means you eat less than you consume through activity.
There are two ways to reach a deficit: either eat less or move more. Ideally, of course, is a combination of both.
Have a look at our body check. It will help you to count your calories: