Pre-req steps for windows update using powershell:

netsh winhttp set proxy "xxxxxxx:80" # use proxy if any

Set-ExecutionPolicy -ExecutionPolicy RemoteSigned -Scope CurrentUser

Install-PackageProvider -Name NuGet

Install-Module PSWindowsUpdate

Add-WUServiceManager -MicrosoftUpdate

Install-WindowsUpdate -MicrosoftUpdate -AcceptAll -AutoReboot | Out-File "D:\MSUpdates.log" -Force