First, those forums are English, please be sure to post in English, or to provide a translation of your message.
I've edited your post to add a google translation of it.
I'm not very clear about what you are asking.
Make sure to check the "Loader style" property of your project.
By default, the splash screen is the one of Construct 3, you can modify it.
If you are talking about the icon of the application, you need to modify it in the icons folder, before export.