best response confirmed by melkinsco (Contributor)
Solution
Hi @melkinsco

See here:

https://docs.microsoft.com/en-us/MicrosoftTeams/private-channels

By design, they aren't visible in the SharePoint admin centre. So, if you can do it, you would need to do so through Powershell. SharePoint Site Collection Limits apply

Best, Chris
www.000webhost.com