Widget Register & Use

/*******Register WIDGET************/

function create_widget( $name, $id, $description ) {

    register_sidebar(array(
        'name' => __( $name ),
        'id' => $id,
        'description' => __( $description ),
        'before_widget' => '<div class="widget">',
        'after_widget' => '</div>',
        'before_title' => '<h4>',
        'after_title' => '</h4>'
    ));

}

create_widget( 'Front Page Left', 'front-left', 'Displays on the left of the homepage' );
create_widget( 'Front Page Center', 'front-center', 'Displays in the center of the homepage' );
create_widget( 'Front Page Right', 'front-right', 'Displays on the right of the homepage' );
create_widget( 'Page Right', 'page-right', 'Displays on the right of the page' );
create_widget( 'Blog Right', 'blog', 'Displays on the right of the blog page' );


//Call the Sidebar

<div class="col-md-3 page_widget">
      <?php if (!dynamic_sidebar('blog')):?>
          <h2>Widget Alert</h2>
          <p>Please add your widget from widger section</p>
       <?php endif;?>
</div>