Where is joomla main page

Solution 1:

Joomla doesn't contain any html files for displaying content, the only html files you will find are blank.

Joomla uses 2 index.php files. There is one in the template folder where all the HTML, CSS and Javascript is pushed to and the other is in the root of your Joomla site where all applications get pushed to one loaded.

When you view the page source code for a Joomla site, you are simply viewing the structure that has been pushed to the index.php file from various locations, such as from modules and components.

Update

Ok, I think this might be best done in the index.php file of your template. First, in the Joomla backend, get the ID of the menu item that link to the page that you wish to use for your code. Once done, add the following code to the index.php:

<?php

$app = JFactory::getApplication();
$doc = JFactory::getDocument();
$menu = $app->getMenu()->getActive()->id;

if ( $menu == 1) { // change 1 to the ID that you got from the Menu Manager
    $doc->addStyleDeclaration('
        //css goes here
    ');
    $doc->addScriptDeclaration('
        //javascript code goes here
    ');
    ?>

    <p>hello world</p>

    <?php
}

?>