You will need to use Powershell to do that.
[System.Reflection.Assembly]::LoadWithPartialName("System.Windows.Forms")
$process = Start-Process "PkgMgr.exe" -PassThru
$StartTime = Get-Date
Write-Host "You have 15 seconds to do something."
while ($true) {
if ($process.HasExited) {
Write-Host "It ended."
break
}
Start-Sleep 5
Write-Host "Testing."
$ts = New-TimeSpan –Start $StartTime –End (Get-Date)
if ($ts.TotalSeconds -gt 15) {
$oReturn=[System.Windows.Forms.Messagebox]::Show("What is taking so long??????")
Write-Host "You took too long."
$process.Kill()
break
}
}
This site shows how to generate a prompt.
https://michlstechblog.info/blog/powershell-show-a-messagebox/