Widget Option is Missing

Put this lines of code in function.php

if (function_exists("register_sidebar")) {
register_sidebar();
}

Put this to sidebar.php

<?php if ( !function_exists('dynamic_sidebar') || !dynamic_sidebar() ) : ?>
<?php $image = new WP_query ('showposts=1');
if(have_posts()) : while($image->have_posts()) : $image->the_post; ?>

  <a href="https://wordpress.stackexchange.com/questions/115901/<?php the_permalink() ?>" rel="bookmark" title="Permanent Link to 
 <?php  the_title_attribute(); ?>"><?php postimage(); ?></a>

 <?php endwhile; endif; rewind_posts; ?>