so its not about reading a xml file, but to read the memory or download a file.

if so, you need to tell, what memory.
usually we get that info from a website. if so, you need to learn how to "download" a file.
theres many examples for that as well.

first thing:
- search how to download a file from a website.

its illogical that you have a xml file in memory.

so important that you write the RIGHT question.