SharePoint Online Powershell - Management Shell

The following are some good sites on SharePoint Online PowerShell/Management Shell:
Get started with SharePoint Online Management Shell
https://learn.microsoft.com/en-us/powershell/sharepoint/sharepoint-online/connect-sharepoint-online

SharePoint Powershell:
https://learn.microsoft.com/en-us/powershell/sharepoint/

Intro to SharePoint Online Management Shell:
https://learn.microsoft.com/en-us/powershell/sharepoint/sharepoint-online/introduction-sharepoint-online-management-shell

Microsoft.Online.SharePoint.PowerShell:
https://learn.microsoft.com/en-us/powershell/module/sharepoint-online/?view=sharepoint-ps