By default WordPress adds a comment box on all posts and pages but sometime when you use WordPress as a CMS you may want to disable comments on some pages. But how to do it, please take a look the below code,
Goto > Appearance > Editor > page.php and locate
<!--?php comments_template( '', true );?-->
and replace it with following code
<!--?php if ( is_page(array(111,12,55))) { comments_template( '', true ); }?-->
Please note: replace 111,12,55 with your page ID, it’ll only display comments on that particular pages which ID you mentioned in this code.