Absolutely lost on this one. Our Backend uses c# with .NET, our Front end uses Angular with DevExtreme. Node.JS is not being used for the Angular side as far as I'm aware, our project lead wants me to figure out how to integrate Docusign onto our Web app.
Do you use Visual Studio? already have a project for your back-end? If you do, just go to add a new nuget package and search "DocuSign" I assume you wanted the eSignature functionality, that would DocuSign.eSign.dll Once you add it though, you'll get access to the functionality, but you still need a few things. To set up your OAuth quickly/easily, highly recommend you use the Quickstart, it will generate a separate C# project for you, but then you can just copy/paste the relevant code+configuration to your existing project.