Have to add the codes in functions.php of active theme in wordpress

// Add custom statuses to the list of WC Order statuses
add_action('init', 'add_custom_order_statuses');
function add_custom_order_statuses() {
    // Register "Open Order" status
    register_post_status('wc-open', array(
        'label'                     => _x( 'Open Order', 'Order status', 'woocommerce' ),
        'public'                    => true,
        'exclude_from_search'       => false,
        'show_in_admin_all_list'    => true,
        'show_in_admin_status_list' => true,
        'label_count'               => _n_noop( 'Open order <span class="count">(%s)</span>', 'Open Orders <span class="count">(%s)</span>', 'woocommerce' )

// Add custom status to the list of WC Order statuses
function add_custom_order_status_to_order_statuses( $order_statuses ) {

   $order_statuses['wc-open'] = _x( 'Open', 'Order status', 'woocommerce' );
    return $order_statuses;

add_filter('wc_order_statuses', 'add_custom_order_status_to_order_statuses');
// Display custom status on the Edit Order page
function display_custom_order_status( $order_statuses ) {
        .column-order_status mark.order-status.wc-open::before {
            content: '\f534' !important;

***** Sometime the custom order list may appear after adding new order and changing to new status by admin dashboard.

By toihid