Asking only 40 min later doesn't help, takes time for people to see this...
But if you don't have BBM installed on your phone go to your browser and go to bookmarks - under "Blackberry Bookmarks" folder there is "Home Page" will take you to mobile.blackberry.com.
If you don't have DM you will have to go to the blackberry site and download it, and also download the new OS when you do the update it should install BBM if it doesn't after the update you will have to go in manually and install BBM