Hello @maxcavalli-nl,
To setup the front page of your website like in the theme demo with the WEN Business Pro theme, you will firstly need to create and set a static front page in your Admin Dashboard > Appearance > Customize > Static Front Page > Front page displays option.
The front page sections in the theme are displayed with widgets available in the theme. After setting a static front page, go to your Admin Dashboard > Appearance > Customize > Widgets > Front Page Widget Area and choose the widgets you like to display in your front page. Each widget can be setup accordingly with your desired content. Save and publish your changes to see the changes in live site front page.
You can also follow the official theme documentation for the theme for step by step instructions with screenshots to setup theme as in the demo at :
https://themepalace.com/instructions/themes/wen-business-pro/
Also, if you are still having trouble with theme setup, please write back to us for any further queries / issues specifying the sections you are having trouble to setup with your Website URL.
Hope this Helps,
Best Regards !!