This article assumes that you have already made a connection to Teams via the PowerShell console.
Assigning a number (DID) to a standard user
Ensure the user is already setup for Teams voice {LINK TO FAQ}
$user = "user@domain"
Set-CsUser -Identity $user -OnPremLineURI "tel:+61xxxxxxxxx"
Alternatively:
Set-CsUser -Identity user@domain -OnPremLineURI "tel:+61xxxxxxxxx"
Assigning to a resource or service user
$resourceuser = "resource_name_aa@domain"
Set-CsOnlineApplicationInstance -Identity $resourceuser -OnpremPhoneNumber +61xxxxxxxxx