Adding read more link

I am using elbee-elgee theme i want to Modiy the theloop.php file so that the postinfo is displayed on another as whole post like read more link
I have tried everything even changing the content with the excerpt and having the function function.php file my requirement is to get read more link without putting the more tag manually in the post i am posting the code here

<?php
	/* Start The Loop */ if (have_posts()) { while (have_posts()) { the_post(); ?>
		<?php /* Permalink navigation has to be inside the loop */ if (is_single()) get_template_part('navigation'); ?>
		<div id="post-<?php the_ID(); ?>" <?php post_class(); ?>>
			<?php lblg_before_post_title(); ?>
			<?php if( !is_single() && !is_page() ) { ?><h2><a href="<?php the_permalink() ?>" rel="bookmark" title="Permanent Link to <?php echo strip_tags(get_the_title()) ?>"><?php the_title(); ?></a></h2>
			<?php } else { ?><h1><?php the_title(); ?></h1><?php } ?>

			<?php lblg_before_itemtext(); ?>
			<div class="itemtext">
				<?php
				if ( is_archive() or is_search() or is_tag() ) {
					the_excerpt();
				} else {

						the_excerpt();
				}
				wp_link_pages( array( 'before' => '<div class="post-pagination">Pages: ', 'after' => '</div>', 'next_or_number' => 'number'));
				?>
			</div>
			<?php lblg_after_itemtext(); ?>
			<!--
				<?php trackback_rdf(); ?>
			-->
		</div>
	<?php } /* End while */?>
	<?php if(is_home() || is_archive()) get_template_part('navigation'); ?>
	<?php } /*End loop*/ ?>

Thank you in advance