file is a script file, but it's usually distributed (such as with nVidia) without the executable bit set. If this is the case with yours, you must first make the file executable and then run it.
Open a terminal window and do the following:
First change to the directory where you downloaded the file. Assuming it's in the Download directory of your HOME directory:
BASH replaces the ~
character with your $HOME environment variable. This variable is set to /home/username
Since you did not give the full name of the file, let's assume it's silentmagic.run. To make the file executable, enter the following command in the terminal window:
chmod +x silentmagic.run
Now run the file as the superuser, enter your password when prompted:
sudo sh silentmagic.run
This will execute the .run file and install the driver. Note though, there may be some options that you may need to specify. You may be able to get help with:
sh silentmagic.run --help
Hope this helps.