Adding Navbar to Page.php

Hope this is in the right place.

I am trying do this without knowing if it’s possible (as usual haha) but what I have done so far seems to work up to a point.

I’m using the 2012 theme (with child) what I want to do is put the standard navbar menu on the home page template ONLY.

So taking the bull by the horns, I took the navbar code from the header.php file and pasted it into the page-templates/front-page.php and thought that would do the trick (poor fool that I am)

Although it has worked somewhat in that it has put all the navigation links in a vertical list on the front-page.php but…

… unlike me I’m sure you coders will know what the problem is going to be viz…

I have lost the horizontal style from the css somewhere along the way and of course the menu Javascript is not working either.

Yet again I have no idea how to put this right, if some valiant soul can please help me get this working correctly I will be eternally grateful.
Apart from jumping off a bridge, what are my next steps?

======================

This is the code snippet from the header.php I pasted in

<nav id="site-navigation" class="main-navigation" role="navigation">
			<button class="menu-toggle"><?php _e( 'Menu', 'twentytwelve' ); ?></button>
			<a class="assistive-text" href="#content" title="<?php esc_attr_e( 'Skip to content', 'twentytwelve' ); ?>"><?php _e( 'Skip to content', 'twentytwelve' ); ?></a>
			<?php wp_nav_menu( array( 'theme_location' => 'primary', 'menu_class' => 'nav-menu' ) ); ?>
		</nav><!-- #site-navigation -->

this is the code that is in the front page.php template to save you lookinh it up.

<?php
/**
 * Template Name: Front Page Template
 *
 * Description: A page template that provides a key component of WordPress as a CMS
 * by meeting the need for a carefully crafted introductory page. The front page template
 * in Twenty Twelve consists of a page content area for adding text, images, video --
 * anything you'd like -- followed by front-page-only widgets in one or two columns.
 *
 * @package WordPress
 * @subpackage Twenty_Twelve
 * @since Twenty Twelve 1.0
 */

get_header(); ?>

	<div id="primary" class="site-content">
		<div id="content" role="main">

			<?php while ( have_posts() ) : the_post(); ?>
				<?php if ( has_post_thumbnail() ) : ?>
					<div class="entry-page-image">
						<?php the_post_thumbnail(); ?>
					</div><!-- .entry-page-image -->
				<?php endif; ?>

				<?php get_template_part( 'content', 'page' ); ?>

			<?php endwhile; // end of the loop. ?>

		</div><!-- #content -->
	</div><!-- #primary -->

<?php get_sidebar( 'front' ); ?>
<?php get_footer(); ?>

and this is where I have pasted the header code into front page.php

get_header(); ?>

<script src="<?php echo get_template_directory_uri(); ?>/js/html5.js" type="text/javascript"></script>

<?php wp_nav_menu( array( 'theme_location' => 'primary', 'menu_class' => 'nav-menu' ) ); ?>

<nav id="site-navigation" class="main-navigation" role="navigation">
			<button class="menu-toggle"><?php _e( 'Menu', 'twentytwelve' ); ?></button>
			<a class="assistive-text" href="#content" title="<?php esc_attr_e( 'Skip to content', 'twentytwelve' ); ?>"></nav><!-- #site-navigation -->

<?php _e( 'Skip to content', 'twentytwelve' ); ?></a>
</nav><!-- #site-navigation -->

	<div id="primary" class="site-content">
		<div id="content" role="main">

			<?php while ( have_posts() ) : the_post(); ?>
				<?php if ( has_post_thumbnail() ) : ?>
					<div class="entry-page-image">
						<?php the_post_thumbnail(); ?>
					</div><!-- .entry-page-image -->
				<?php endif; ?>

				<?php get_template_part( 'content', 'page' ); ?>

			<?php endwhile; // end of the loop. ?>

		</div><!-- #content -->
	</div><!-- #primary -->

Standing by, but not holding my breath in case I have posted in the wrong place ??