Hello @Sritharini Radhakrishnan
You can find then Install EXE (offline installer) at: https://support.microsoft.com/en-us/topic/microsoft-net-framework-4-8-offline-installer-for-windows-9d23f658-3b97-68ab-d013-aa3c3e7495e0
Maybe the Developer pack can have different file properties: https://dotnet.microsoft.com/download/dotnet-framework/thank-you/net48-developer-pack-offline-installer
Hope this helps in your case.