You can add images to your mailing or landing page using the file manager and either insert images that you have already added or upload and insert new ones using the file manager. 
The drag & drop editor allows you to edit the width of your image, link the image, and change other properties in the Content Properties. You can also Apply effects & more to edit your image using a variety of editing tools, filters, stickers, and more. When you edit an image using these tools, the original image will not be modified; a new copy of your edited image will be generated