cloned category.php doesn't load a post!

Hello People!

I want to setup a template file in my theme, which shows ALL the posts of my site.

i’ve cloned category.php, named it into “grid.php”, gave it the template-name “Grid” inside the code and created a site with the new template “Grid”.

But now: It doesn’t load any post! I want it to load all posts on my site. How can i ged rid of this?

Thanx in advance!!

Here’s the URL: https://www.timrodenbroeker.de/grid/

And this is the code:

<?php/*
Template Name: Grid
*/

?>

<?php get_header(); ?>

<?php if ( have_posts() ): ?>

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

<article>

        <div class="articlethumb"><?php if ( has_post_thumbnail()) : ?>
<?php

// Wenn Kategorie 20 oder 35
if (in_category( "20" ) or in_category( "35" )) {

    // Wenn Kategorie 20
    if (in_category( "20" )) {
        the_post_thumbnail();
    }
    // Wenn Kategorie 35
    if (in_category( "35" )) {
        echo '<div class="quadrat"><a href="';
        the_permalink();
        echo '">';
        the_post_thumbnail();
        echo '</a></div>'."\n";
    }
}
else {  // Die restlichen
        echo '<a href="';
        the_permalink();
        echo '">';
        the_post_thumbnail();
        echo '</a>';
}
?>
<?php endif; ?>

    </div>

<div class="articledesc"><?php the_title(); ?></div>

    </article>

<?php endwhile; ?>
</ol>

<?php else: ?>
<h2>No posts to display</h2>
<?php endif; ?>

<div class="bottomnav"><a class="super next"><?php posts_nav_link(' / ','Zurück','Weitere Projekte'); ?></a></div>

<?php get_footer(); ?>