Var_dump debug not working

Hi, When i put this in my plugin.php file outside of functions, it works. When I put them in a function, I just get a white screen surrounded by the admin panel. I want to `change the value of $posts to $myvariable

$posts = get_posts();
echo '<pre>';
var_dump($posts);
echo '</pre>';
die();

Also when I turn debug on on my local site, I don’t get the info at the top of the site. It simply looks the same. I do get the log turned on.

I need to debug, I need these tools or I feel I won’t get very far.

Can you use var_dump inside a function in a plugin? How else could you read the value of variables while the code runs and requests are sent?

Here’s my code in the WP-config.php file in case you’re doubting me, not inside comments in the correct folder for my local site. I’m using local by flywheel btw.

define( 'WP_DEBUG', true);

define( 'WP_DEBUG_LOG', true);

define( 'WP_DEBUG_DISPLAY', true);

Thank you guys