How to add ad code to top of pages and top of posts?

Hi. I’m using an ad manager for ads on my site, and I want to add a banner image to the bottom and top of my pages and posts. I want different ad code for pages vrs posts.

I’ve created a child theme with single.php and page.php which I can now edit. I know I need to add the ad code somewhere but I’m not sure how or where.

The ad code looks like this: [sam_pro id=”0_1″ codes=”true”]

I’m reading a tutorial about this and it says to add the code right after this code: <?php while ( have_posts() ) : the_post(); ?>

But I cannot find that code. Also do I just add the code as is, or do I need to wrap it in certain tags? What am I doing wrong? Thanks! –eric