Thank you for reaching out. We're able to help you here in English. You can translate our answer here.
Did you remove the background with Quick Actions or while editing your project? Can you share the original image you uploaded to remove the background?
With Quick Action, the image is kept the same size. You can try it here. If you remove the background of an image you upload to a project. The element will be shown on the canvas, but the area will not be reduced. The area on the background is the area of the canvas. You can customize the size of it by clicking on resize, as shown on the screenshot attached.