test.php

<?
$paged = get_query_var('paged') ? get_query_var('paged') : 1;
$query = new WP_Query([
  'post_type' => ['articles', 'projects', 'tips'],
  'orderby' => 'date',
  'posts_per_page' => 7,
  'paged' => $paged
]);
?>

<? while($query->have_posts()): $query->the_post() ?>
  <article class="post">
    <h2><? the_title() ?></h2>
    <p><? the_excerpt() ?></p>
    <ul>
      <? foreach($categories as $cat): ?>
      <li class="category"><a href="#"><?= $cat->name ?></a></li>
      <? endforeach ?>
    </ul>
  </article>
<? endwhile ?>