A cloud-based service included in Microsoft 365, delivering scalable messaging and collaboration features with simplified management and automatic updates.
Yes, the syntax is correct. You can always add the -WhatIf parameter to preview the cmdlet result, without actually executing it.
As for creating Unified group, use this:
New-UnifiedGroup -Name "test UG" -DisplayName "TEST UG" -PrimarySmtpAddress "******@contoso.com"