http://community.idera.com/powershell
https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_functions?view=powershell-5.1
Also these courses are supercool:
https://mva.microsoft.com/en-us/training-courses/getting-started-with-powershell-3-0-jump-start-8276
https://mva.microsoft.com/en-us/training-courses/advanced-tools-scripting-with-powershell-3-0-jump-start-8277?l=WOWaGUWy_8604984382
https://mva.microsoft.com/liveevents/powershell-jumpstart
Please remember to "Mark as answer" if it helps. Thank You.
