Remove “Category: Title” from top of category page

Hello,

I am new the WordPress operating system. I created different “pages” by making them categories instead of “menus” or “pages” because I wanted to be able to click on the title in the navigation bar at the top and have a list of posts related to that one topic on the page. However, in doing so, I cannot remove the “Category: Book Reviews” from the top of the page. I do not want this to show up on any of the pages I have, so I need to know how to get rid of it. I’ve looked on ample forums and websites on how to put Custom CSS into the theme, but no code is working for me. I even installed the “Remove Category Word From Title” plugin by Ausaf Malik, but of course that only removed “Category:” and left “Book Reviews.” Is there a code I can use for this theme to remove the whole title, or a plugin that I can install?

Also, if possible, I would like code or a plugin to remove the category title from the top of every individual post as well.

Thank you,
Kathleen

The page I need help with: [log in to see the link]