Adding a Sidebar into Theme

My websites (www.exchangecapital.com) theme was custom built by a developer who did not add any sidebars–or at least any editable ones. In my functions.php file I see this code registered:

function exchangecapital_widgets_init() {
register_sidebar( array(
‘name’ => __( ‘Menu Sidebar Widget Area’ ),
‘id’ => ‘sidebar-menu’,
‘before_widget’ => ‘<div class=”icons”>’,
‘after_widget’ => ‘</div>’,
‘before_title’ => ”,
‘after_title’ => ”,
) );
}
add_action( ‘widgets_init’, ‘exchangecapital_widgets_init’ );

However, this sidebar contains only a text widget that makes the three buttons seen on the left hand side of the page–therefore not much customization can be done here.

Without changing my theme, I’d like to add a sidebar into my websites current theme for customization purposes.
Specifically, I’m hoping to create a sidebar on the right hand side of my blogs page (https://www.exchangecapital.com/wealthy-street-blog/) to add some widgets and create a better look all around.

Can anyone help me out with the implementation? I’m not much of a coder, but have a decent grasp on it. I think with some direction I should be able to edit the themes files to get things rolling. ANY advice or feedback is appreciated. Thanks in advance!