You need to create a folder called "Fleet" in core/module and inside that folder make a file called "Fleet.php" then open the fleet.php and paste the above code in there. Also, you need to place the "fleet_main.tpl" in you skin folder or in core/templates if you're using the default skin. Remember, the module folder and the file inside that are case sensitive. To create a link to call the module use the following code:
< a hre="<?php echo url('/fleet') ;?>">Fleet Page</a>