===== Add an existing user to Local Administrators group via Powershell =====
Add an existing local user to the ''Administrators'' group.\\

==== Command ====
  # Replace with your local user ID or AzureAD/Entra ID - prefix with 'AzureAD\' for latter case
  $User = "username"
  Add-LocalGroupMember -Group "Administrators" -Member $User
  
  # Alternative script for AzureAD/Entra
  net localgroup administrators AzureAD\<username> /add