Call webservice Extranal and get Data to NAV 2013

Hi Everybody

I currently have small shops in the distance.
When consumption goods on a website system. I want to get on-time data for every inventory of materials.
I want to get data remotely via Webservice and then put it into NAV to post.
Now I have Webservice. But I don't know how to get the data into the NAV.
Please guide me to help. Thank you very much

<?xml version="1.0" encoding="utf-8"?>
<soap:Envelope xmlns:xsi="" xmlns:xsd="" xmlns:soap="">
    <GetLatestExtractResponse xmlns="">

Best Regards,