Remove single page for custom post type

Because you are linking to external news articles you would like to prevent users from getting to the /news-article/article-title/ url that is created for a new post and would have no real content?

You could do something like this: How to disable the single view for a custom post type?

The code below is from that answer. Add it to your functions.php, making sure to change news_article to the actual post type slug. This should 301 redirect a user trying to hit that single post. You may want to test this first using 302 as many browsers will cache a 301 and can be difficult to clear out.

It defaults to 302, so remove the , 301 to set it to default if you’d like to try with a 302.

add_action( 'template_redirect', 'news_article_redirect' );

function news_article_redirect() {
  $queried_post_type = get_query_var('news_article');
  if ( is_single() && 'news_article' ==  $queried_post_type ) {
    wp_redirect( home_url(), 301 );
    exit;
  }
}