How do I list all sites in my site collection in SharePoint Online?
I am not trying to view the 'Site Hierarchy' - this lists subsites of the site I'm viewing at the time, not all sites in the collection. When I go to my 'main' site (https://companyname.sharepoint.com/), I can see subsites of that site, but not all sites that have been created by clicking on the 'Sharepoint' at the top of the screen and then 'Create Site'. These appear as https://companyname.sharepoint.com/sites/SiteName.
I am not trying to view 'Sites and Workspaces' - this also only lists the subsites of the current site, not all sites created as described above.
I'd prefer something that didn't involve PowerShell - as that involves me booting a Windows system to use it.
Are these actually all different site collections? If so, how do I get to the admin centres for them? The SharePoint admin centre linked from the Office365 admin portal only shows four site collections: