Hi @Baybbtout, you can also search through your child theme file for any of these strings which are normally part of the loop: the_title, have_posts, the_post, $post…
If you don’t find any of them, maybe they are still only located in your parent theme. Like @elliot said, there is not necessarily a loop file. Sometimes, a file with loop code is included via the get_template_part WordPress function. Otherwise, there will be no particular file insulating this particular part of code.
But firstly, follow @elliot advice by searching in the single.php and page.php files.
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