A group of Microsoft Products and technologies used for sharing and managing content, knowledge, and applications.
Hi GymnophoriaUK,
You can try the following URL to access the default team site.
https://contoso.sharepoint.com (Change “contoso” to your own company domain)
Actually, I found a more easy way to share the group site to the whole organization. But it only give people access to the contents in the site. They cannot access the group conversions and calendars. Go to the group site > click the Gear and select Site permissions > select Invite People > click Share site only > enter Everyone.
Thanks,
Ran