By registering the following shortcode in your functions.php the theme, you can show the send SMS form for your visitors by this shortcode: [wpsms_send_form]
The receiver of SMS is the admin mobile number, you can change the receiver number if you wish!
add_shortcode('wpsms_send_form', function () {
?>
<form method="post">
<?php wp_nonce_field('send_sms_nonce', 'wpsms_nonce'); ?>
<textarea name="content"></textarea>
<button type="submit">Send SMS!</button>
</form>
<?php
if (isset($_POST['wpsms_nonce']) && wp_verify_nonce($_POST['wpsms_nonce'], 'send_sms_nonce')) {
$adminMobileNumber[] = \WP_SMS\Option::getOption('admin_mobile_number');
wp_sms_send($adminMobileNumber, sanitize_text_field($_POST['content']));
wp_safe_redirect( wp_get_referer() );
exit;
}
});