As a SharePoint admin or Office365 admin go to https://{tenantname}-admin.sharepoint.com/_layouts/15/online/SiteCollections.aspx. Replace {tenantname} by your tenant, without using curly brackets.
In the modern admin center
- In Site manangement select Create site
- Choose classic site in the side panel
- Select Teamsite (classic version) from the dropdown
- Fill out the form and create the site. Select complete to create the site