When first using the nutrition app, you are asked to create a nutrition plan. Based on a few personal details about your health and lifestyle, the system creates a nutrition plan for you that will help you reach the stated goal.
This also includes a certain amount of daily calorie intake. When you would want to change this amount for whatever reason, you can do this in your nutrition diary.
Go to the nutrition app, click the tab nutrition diary and you will see your daily amount stated at the top left of the screen. Next to that "daily advice" is an "edit" button. Here you are able to put in a new amount of calories. To ensure a healthy lifestyle, make sure you don't adjust the amount drastically at once.