Use this simple Powershell command script to find your DotNet version installed on your machine
Get-ChildItem 'HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP' -Recurse | Get-ItemProperty -Name version -EA 0 | Where { $_.PSChildName -Match '^(?!S)\p{L}'} | Select PSChildName, version
also you can use this command to get list of all software installed on your machine too
Get-CimInstance -ClassName Win32_Product | Select-Object name, vendor