I recommend starting here
https://jsreport.net/learn/dotnet
perhaps with this example
https://github.com/jsreport/jsreport-dotnet-example-webapp
This example gives you an idea how to integrate local jsreport without using node.
However, it is just one way.
You can also start extra service - jsreport or jsreportonline and integrate from .net using jsreport.Client
This separation is more complex for the set up, but a bit cleaner on the other hand.
It is up to you what you will prefer.