Hello @heather23,

To remove the “Archives:” in archive page, you have to activate the child theme.

Please refer to below-given link on how you can create and activate the child theme.

http://wptravel.io/how-to-create-a-child-theme/

Now add below-given code in your child themes functions.php file.

function construction_base_pro_child_custom_cat_title_removal ($title) {

    if ( is_category() ) {

            $title = single_cat_title( '', false );

        } elseif ( is_tag() ) {

            $title = single_tag_title( '', false );

        } elseif ( is_author() ) {

            $title = '<span class="vcard">' . get_the_author() . '</span>' ;

        } elseif ( is_archive() ) {

        	$title = preg_replace('/^\w+: /', '', $title);

        }

    return $title;

}

add_filter( 'get_the_archive_title', 'construction_base_pro_child_custom_cat_title_removal

Hope this helps.

If you have any issue further please let us know.

Thank you.

Regards!!