Help with query

Yes you can do this. Here’s your PHP code wrapped inside an HTML structure with proper formatting and comments, ready to be used in a WordPress template file (like front-page.php or home.php). This example includes the logic to:

Show 1 most recent post from specific categories first

Then show 10 most recent posts from all categories

Then show 10 most recent posts per category

<?php
// 1. Show 1 most recent post from specific categories
$specific_cat_ids = array(3, 5, 7); // Replace with your category IDs

$args = array(
    'posts_per_page' => 1,
    'category__in' => $specific_cat_ids,
    'orderby' => 'date',
    'order' => 'DESC',
);

$featuredQuery = new WP_Query($args);
if ($featuredQuery->have_posts()) {
    echo '<section class="featured-post">';
    echo '<h1>Featured Post</h1>';
    while ($featuredQuery->have_posts()) {
        $featuredQuery->the_post(); ?>
        
        <h2><a href="<?php the_permalink(); ?>"><?php the_title(); ?></a></h2>
        <div id="humbnail">
            <?php if (has_post_thumbnail()) {
                the_post_thumbnail();
            } ?>
        </div>
        <div class="content">
          <?php the_content('Read More »'); ?>
        </div>

    <?php }
    echo '</section>';
    wp_reset_postdata();
}

// 2. Show 10 most recent posts from all categories
$args = array(
   'posts_per_page' => 10,
);
$customQuery = new WP_Query($args);
if ($customQuery->have_posts()) {
    echo '<section class="all-cats">';
    echo '<h1>Latest Posts</h1>';
    while ($customQuery->have_posts()) : $customQuery->the_post(); ?>

        <article>
          <h2><a href="<?php the_permalink(); ?>"><?php the_title(); ?></a></h2>
          <div id="humbnail">
              <?php if (has_post_thumbnail()) {
                  the_post_thumbnail();
              } ?>
          </div>
          <div class="content">
            <?php the_content('Read More »'); ?>
          </div>
        </article>

    <?php
    endwhile;
    echo '</section>';
    wp_reset_postdata();
}

// 3. Show 10 most recent posts per category
$allcats = get_categories('child_of=".get_query_var("cat')); 

foreach ($allcats as $cat) :
    $args = array(
        'posts_per_page' => 10,
        'category__in' => array($cat->term_id)
    );

    $customInCatQuery = new WP_Query($args); 
    if ($customInCatQuery->have_posts()) : 
        echo '<section class="category-posts">';
        echo '<div id="posts-header-container"><h1><span>Recently from '.$cat->name.'</span></h1></div>';
        while ($customInCatQuery->have_posts()) : $customInCatQuery->the_post(); ?>

            <article>
              <h2><a href="<?php the_permalink(); ?>"><?php the_title(); ?></a></h2>
              <div id="humbnail">
                  <?php if (has_post_thumbnail()) {
                      the_post_thumbnail();
                  } ?>
              </div>
              <div class="content">
                <?php the_content('Read More &#187;'); ?> 
              </div>
            </article>

        <?php
        endwhile; 
        echo '</section>'; 
    else : 
        echo '<p>No post published in: '.$cat->name.'</p>';                
    endif; 
    wp_reset_postdata();
endforeach; 
?>

How to Use:
Replace the category IDs in $specific_cat_ids = array(3, 5, 7); with your desired category IDs.

Save this as your homepage template or insert the PHP part into your existing homepage template.