@Dheeraj ,
It appears that you would like to create a C# function and a powershell function inside the same function app which is not possible. While creating the function app, you can choose either one of the languages (C# or Powershell) but not both. This is by design, the C# functions gets executed by dotnet worker and powershell functions gets executed in powershell workers.
If you are using webhooks/http triggers, you can create separate Function Apps for dotnet and powershell and make http calls between them.
https://learn.microsoft.com/en-us/azure/azure-functions/functions-bindings-http-webhook-trigger?tabs=csharp
I hope this helps!
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