Use Windows Explorer, find the file, then double click on the file name. The appropriate program will load the file. But hey, if you're really new to computing, even the above is likely to make little sense. If this person had sent me a note and asked that question, I would have answered. And with more detail than above.
Nobody wants to look foolish or amateurish or both.
Well, now there's a great place for newbies to hang out. It's the Newbie Club. And it was put together by two top type people who really know their business, Joe Robson and Tom Glander. While the site is new, they already have some neat stuff available. Including a forum in which you can lurk and find answers to questions bothering you.