HTTP Error 500.19 - Internal Server Error Sitecore identity server

  

If you are facing the below issue with Sitecore 9, 10, or 10.1. Then it is recommended to install the below dependency to resolve this issue.

https://dotnet.microsoft.com/download/dotnet-core/2.2

But before installation, I would suggest verifying existing .netcore in your system
by running dotnet --info on PowerShell (as admin)

Hope this will resolve your issue.



There is also another possibility for this issue that from 
Turn Windows feature on or off - choose below options

You may also face still face the same issue with Sitecore 10.2 in that case you must be required to install as this is recommended by Sitecore https://doc.sitecore.com/xp/en/developers/102/sitecore-experience-commerce/system-requirements.html

Please go to this link to download https://dotnet.microsoft.com/download/dotnet-core/3.1

Hope the above options will help you to fix this issue.