I am making an employment form and I need to send a PDF file

I am making a form, with an input for PDF , validating that all the fields are filled in order to be sent to a predetermined mail, but when the mail arrives the file of the > PDF does not arrive as it should.

The code is as follows:

window.onload = function() {
    var $form2 = $('#trip');
    function validateEmail(email) {
        var re = /^(([^<>()\[\]\.,;:\s@"]+(\.[^<>()\[\]\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
        return re.test(String(email).toLowerCase());
    }
    $('#trip').submit( function(e) {
        e.preventDefault();
        var campo_email = $('input[name="email"]').val();
        var campo_name =$('input[name="name"]').val();
        var campo_coment =$('textarea[name="coment"]').val();
        var campo_cv = $('input[type="file"]')[0].files[0].size;

        if(campo_email && campo_name && campo_coment && campo_cv){
            if(validateEmail(campo_email) === true && campo_name && campo_coment && campo_cv){
                /* EMAIL */
                    var datos = { action:'siteWideMessage', nombre:campo_name, comentario:campo_coment, email:campo_email, fileCurriculum:campo_cv };
                    $.post('<?php echo admin_url("admin-ajax.php"); ?>', 
                        datos, function(response) {
                        console.log(response);
                    });
                /* END EMAIL */
                $("#modal-up").hide();
                alert("Message sent!");
                window.location.reload(false);
            }else{
                alert("The mail is invalid");
            }
        }else{
            alert("Please, complete all the fields");
        }
    })
}

** functions.php code **

/ * SEND EMAIL POPUP * /

add_action( 'wp_ajax_siteWideMessage', 'wpse_sendmail' );
    add_action( 'wp_ajax_nopriv_siteWideMessage', 'wpse_sendmail' );

    function wpse_sendmail()
    {
        $nombre  = $_POST["nombre"];
        $email = sanitize_text_field( $_POST["email"] );
        $comentario  = $_POST["comentario"];
        $fileCurriculum = $_POST["fileCurriculum"];

        // get the blog administrator's email address
        $to = "[email protected]";

        $message = 'Hola mi nombre es  ' . $nombre  . ' y mi correo es ' . $email . ' estoy postulando para ' . $comentario . 'mi Curriculum ' . $fileCurriculum;
        $subject = 'PUESTO DE TRABAJO';
        $headers = "From: <$email>" . "\r\n";

        // If email has been process for sending, display a success message
        if ( wp_mail( $to, $subject, $message, $headers ) ) {
            echo '<div class="mensaje" style="display:none;">';
            echo '<p>Thanks! Your personalised itinerary will be emailed very soon!</p>';
            echo '</div>';
        } else {
            echo 'An unexpected error occurred';
        }
        die();
    }