You Just need to attach the soap service as a connected service in VS. Right Click in your project ==> Add Service Reference ==> Select "WCF Web Service" and follow the form inserting WSDL url or the WSDL xml file. After that all the classes and methods you need (including response class models) will be generated by VS.

You can also use HttpClient passing the xml request in body, but it will require more effort generating class models. If you still prefer this way, vs past special can help you generating the class, for example you can do the calls using postaman, and then copying the xml result pasting with "paste special" in a new class file.