Display only on certain page (custom code)

Hello,

I would like to display the like/dislike only on certain page. I have found the code : https://ww.wp.xz.cn/support/topic/total-number-of-likes-and-dislikes/
But since, I don’t use wp_head() & wp_footer() in my theme, I would like to know what should I add to be able to make it works

Regards,