Hi, may I suggest you pick up a short and quick tutorial on the basics of how to consume a web service? This CP article
] should help too.
However, to answer your questions, when you add web reference to your asp.net project it already creates proxy classed and it uses the WSDL. As a consumer of the service all you need to care about is invoke the service and provide proper parameters as per the contracts and fetch response.
I hope it helps.
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