You're going to be working with variables, arrays, and functions for this one, so be prepared to learn about using those. When learning flash, don't forget about the flash help resource in the program itself. Do a search for XML in the flash help and in the results scroll down to "ActionScript 2.0 Language Reference"--find XML in there and study that to learn the basics of how XML works in flash. The general procedure for XML in AS2 is to create a variable that will hold your XML data, a function loads the XML data into the variable, using scripts like "childNodes", "nextSibling", and "attributes" to drill down into the XML tree and assign the values from your XML into variables and arrays, and then finally take the values in those variables and arrays and use them. The thing that stumped me the most was the asynchronous loading of the XML data which means that the XML does not load in relation to the flash document--it loads at its own pace and actually takes a few milliseconds to complete, so if you load your xml in the first frame and your trying to use data from the xml in the next frame (without a stop inbetween) you're going to find that the variables are undefined because the xml hasn't finished loading yet... the trick is to use a stop which doesn't let the playhead go to the next frame until the xml has finished loading and populating the variables. I think the actual time the xml takes to load is around 1/8 of a second (5 frames at 40fps)--I seriously spent something like 3 or 4 days trying to figure out why my variables kept coming back undefined when my code was right--checking and rechecking my code. Some other useful resources on learning XML in flash are: www.kirupa.com and this page http://www.flashguru.co.uk/links/ where you will find more links to resources.
Good luck.