Hi Sakin, thanks for your help. Meanwhile I found myself a solution. I have add the below code in functions.php from my child theme. I also tested your solution and it worked. Thank you.
function catchflames_post_featured_image() {
// Getting data from Theme Options
global $post, $wp_query, $catchflames_options_settings;
$options = $catchflames_options_settings;
$contentlayout = $options['content_layout'];
$sidebarlayout = $options['sidebar_layout'];
$imagesize = '';
if ( has_post_thumbnail() ) : ?>
<figure class="featured-image">
<a>" title="<?php echo esc_attr( sprintf( __( 'Permalink to %s', 'catch-flames' ), the_title_attribute( 'echo=0' ) ) ); ?>">
<?php the_post_thumbnail( $imagesize ); ?>
</a>
</figure>
<?php endif;