I am executing the below command, i want to fetch the list of licenses using c#
Get-csonlineuser -Identity firstname.lastname@example.org |select-object *policy
So what is your question?
want to fetch the policies fro PSObject to dropdown
You are still no closer to a question here that we could honestly help with... Detail? Context? Existing code? Error? Any of that information would be very helpful for us to help you...
Are you implying that your C# program is calling PowerShell code to retrieve the policy information and you are trying to figure out how to consume the output in your C# program?
If that is the case you would be better off just having C# use the Microsoft.Rtc.Management.ADConnect.Schema.ADOCOnlineUser class directly. That is the class of object returned by Get-CsOnlineUser.