Exclude categories from blog

Add the following code to your theme’s function.php file, or a functionality plugin to modify to exclude categories from your WordPress Blog Page.

/** Exclude certain category from posts */
add_action( 'pre_get_posts', 'be_exclude_category_from_blog' );
function be_exclude_category_from_blog( $query ) {

    if( $query->is_main_query() && $query->is_home() ) {
        $query->set( 'cat', '-XX' );
    }
}