How to "GET" from an xml file?

My company is using a helpdesk/support ticket/eForm program to receive requests, and then manually entering those tasks into smartsheet. The program will allow me to POST the data via XML at the same time as form submission. I am trying to figure out how to automate this so that the data will then automatically be passed on to smartsheet in real time. (I'd like to avoid manually importing the xml file) This doesn't seem like it would be that difficult, but I'm having a hard time finding tutorials or documentation on how to get started. Can someone please point me in the right direction?