wp-theme/single-post.php

<?php
    get_header();
    get_template_part( 'template', 'blogheader' );

    echo '<div class="blog-column row row--content">';

    if ( have_posts() ) {
        while ( have_posts() ) {
            the_post();

            get_template_part( 'content', 'blog' );

        }
    }
    else {
        get_template_part( 'content', 'noposts' );
    }

    echo '</div>';
    
    get_footer();
?>