Forum Discussion
UPDATE: Create Office 365 Groups with team sites from SharePoint home moving beyond First Release
Every Modern Team Site (i.e. connected with a Group) is a root site of a site collection.
If I understand well, you want to create a subsite that looks like a Modern Team Site.
This is not possible OOTB, but you can "mimic" to some degree the look of a Modern Team Site.
This has been discussed in several threads: please do a search.
That's right Salvatore Biscari, mgable_presidio - we haven't updated the sub site creation experience yet so currently your only choices there are "classic" templates (yes, we are working on this - more to share in the new year). As Salvatore notes, most of the modern team site elements are available in the classic team site (modern site contents, document library, site pages w/ client-side web parts, etc.) - and the site by default will inherit permissions of the modern parent site's group.