If you need to found OEM product information in Windows, you can run this powershell command.
Such as serial number / product type / product type or Vendor.
gwmi win32_ComputerSystem | select OEMStringArray
wmic csproduct list /format:list
Get-WmiObject Win32_BIOS | Select-Object SerialNumber
To show the queue of postfix, just run postqueue -p
But if you will like to show the total number of mails in the postfix queue, you can run this streng.
postqueue -p | tail -n 1 | cut -d' ' -f5
You can use this command to get the list of the number of file in current directory
ls -1 ./ | wc -l
Or
ls -1 /var/log | wc -l
to get the number of files in /var/log