How to get the custom field value at thank you page

I adda ed the below code to function.php page and it shows the select box at checkout page fine. But how can i get the value of selected item at the thank you page.

add_filter('woocommerce_checkout_fields', 'custom_override_checkout_fields');

function custom_override_checkout_fields($fields) {
    $fields['billing']['point_side'] = array(
        'label' => __(
            '<strong>Select Where Your Points Should Go</strong>',
            'woocommerce'
        ),
        'placeholder' => _x(
            'custom_field', 'placeholder',
            'woocommerce'
        ),
        'required' => true,
        'clear' => false,
        'type' => 'select',
        'class' => array('form-row-wide'),
        'options' => array(
            'default1' => __('Defult1', 'woocommerce'),
            'ls' => __('Left Side', 'woocommerce'),
            'rs' => __('Right Side', 'woocommerce')
        )
    );

    return $fields;
}

Any helps appreciated.