first you compile your project in MMF. In MMF2, this is under the file menu, in file---> build---> application. It will then ask you where to save this file. Now your game is a .exe; anyone who puts this on their computer to play it needs only to click on the icon. In order to share this online so people can download it, you need a web host.
There are two easy to get ways to host games if you don't want to pay for it. At this website, rapidshare:
http://www.rapidshare.com/
all you need to do is follow the instructions. It will then give you the address link;; copy and paste this, and anyone who clicks on it in their browser will download your game. A better solution, if you have time to set it up, is a googlepages account, which is tied to your gmail.
http://www.gmail.com/
first set up your own gmail account on that site. Its the best free web email out there, so you should have one anyway. Next, visit
http://www.googlepages.com/
from here, while logged into your account, look at the right side of the screen. There is a column saying "Uploaded Stuff". Click on the "Upload" button to upload your game onto google. Once it is finished uploading, right click on the name of your game. Select "Copy Link Address", and now you can paste this address to anywhere you want. This is a direct download address; instead of having to type in codes and wait time on rapidshare, anyone who visits this link will instantly start downloading your game.