<?php get_header(); ?>

<div id="content" class="archive">

<?php if (have_posts()) : while (have_posts()) : the_post(); ?>

<div class="post" id="post_<?php the_ID(); ?>">

<span id="map">/"><?php _e('Home','arthemia');?> » <?php the_title(); ?></span>

<h2 class="title"><?php the_title(); ?></h2>

<div class="entry" style="padding-top:15px;">
<?php the_content(__('<p>Read the rest of this page »</p>','arthemia')); ?>

<?php wp_link_pages(array('before' => __('<p>Pages:','arthemia'), 'after' => '</p>', 'next_or_number' => 'number')); ?>

</div>

</div>

<?php endwhile; endif; ?>

</div>

<?php get_sidebar(); ?>
<?php get_footer(); ?>
------------------------------
Above list is page.php.

I am beginner, able to recoding below;

if page slug is 'forum', <?php get_footer(); ?>;
else if <?php get_sidebar(); ?>
<?php get_footer(); ?>