This will list the 3 most recent posts from the post type us_portfolio.
<?php
$args = array(
'posts_per_page' => 3,
'post_type' => 'us_portfolio'
);
$custom_query = new WP_Query($args);
while ($custom_query->have_posts()) :
$custom_query->the_post();
?>
<div class="image bg-image" style="background-image: url('<?php the_post_thumbnail_url('full'); ?>')"></div>
<?php the_category(); ?>
<h3>
<a title="<?php the_title(); ?>" href="https://wordpress.stackexchange.com/questions/289627/<?php the_permalink(); ?>">
<?php the_title(); ?>
</a>
</h3>
<a href="https://wordpress.stackexchange.com/questions/289627/<?php the_permalink(); ?>">">Read More</a>
<?php endwhile; ?>
We are using WP_query to achieve this.
You can learn more about WP_Query here: https://codex.wordpress.org/Class_Reference/WP_Query