How would I get 1 latest post from a query for 5 posts?

You can use $current_post property of WP_Query

$query_args = array(
    "posts_per_page" => "5"
);

$listedPosts = new WP_Query($query_args);

// the loop

if ( $listedPosts->have_posts() ) {
    while ( $listedPosts->have_posts() ) {
        $listedPosts->the_post();
        if ( (int) $listedPosts->current_post === 0 ) {
          // loop content for hero post
        } else {
          // loop content for remaining posts
        }
    } 
}