Hello, @Krzysztof,
You can try with XStudio feature: https://xstore.helpscoutdocs.com/article/148-xstudio-feature-of-xstore-wordpress-theme and copy/import any section from any demo on your site as per your requirements.
OR you can use this feature: https://www.youtube.com/watch?v=MYei56eV7mU&list=PLMqMSqDgPNmCCyem_z9l2ZJ1owQUaFCE3&index=22
Regards 8Themes Team.