Mix of Customizer default layout and fullwidth without container

In WordPress settings I can use a custom page to replace my default start page. If I create a custom page (e.g. called start page) while using template 6 (no container, no header, no footer) this should result into a fullwith layout without container.
How can I add the default blog post section (masonry design) with last 10 posts to this custom start page? The default start page in Customizer doesn’t allow me to use a layout without container. Therefore I think I habe to use a custom start page based on template 6…

Can you help me, please?

It could be done by the custom CSS.

Could you please send us with your website URL so we can take a closer look?

Thanks.