Это не так сложно в PowerShell.
Что-то вроде ниже должно сработать:
# read the file and use Where-Object to capture only those lines that have 24 words exactly.
# the regex -split uses '\W+', meaning to split each line on (at least one) Non-Word character.
$result = Get-Content -Path 'D:\test.txt' | Where-Object { ($_ -split '\W+').Count -eq 24 }
# output on screen
$result
# write output to new file
$result | Out-File -FilePath 'D:\test24.txt' -Force