how to post data from a php consult to a modal and generate a UPDATE

I am trying to pass data from an external query to a modal to be able to generate an update, but I notice that the variable of said query is not being passed to me, could you help me in what I am wrong, I am starting, my modal

<div id="content">
<button type="button" class="btn btn-danger" id= "hide" onclick="hide()">Close</button>
<form action="addcredits.php" method="POST" id="form1">

    <input class="form-control" placeholder="Ingresa el total de efectivo" name="username" id="username">

    <input type="button" name="btn" value="Ingresar" id="submitBtn" data-toggle="modal" data-target="#confirm-submit" class="btn btn-default" /> 

    <div class="modal fade" id="confirm-submit" tabindex="-1" role="dialog" aria-labelledby="myModalLabel" aria-hidden="true">
        <div class="modal-dialog">
            <div class="modal-content">
                <div class="modal-header">
                    Confirmar
                </div>
                <div class="modal-body">
                    ¿La cantidad ingresada es correcta?
                    <table class="table">
                        <tr>
                            <th>Efectivo</th>
                            <td id="uname"></td>
                        </tr>
                    </table>
                </div>
                <div class="modal-footer">
                    <button type="button" class="btn btn-default" data-dismiss="modal">Cancel</button>
                    <input class="form-control" type="text" name="business_name" value="<?php echo $consult["id_students"]; ?>"  placeholder="<?php echo $consul['id_students']; ?>">
                    <p><?php echo $consult["id_students"]; ?></p>
                    <p><?php echo $consult["id_students"]?></p>
                    <a href="#" id="submit" class="btn btn-success success">Submit</a>
                </div>
            </div>
      </div>
  </div>

</form>

and this is my extern consult

<?php
include("conection.php");


echo 
'
<div class="container-fluid ">  
    <div class="row">
        <div class="col-lg-12">
            <table class="table table-hover">
                <tr >
                    <th scope="col">Grupo</th>
                    <th scope="col">Nombre</th>
                    <th scope="col">Créditos</th>
                </tr>
            ';

            $accion = mysqli_real_escape_string($con,$_POST['accion']);
            if($accion == 4)
            {
                $mi_busqueda =  mysqli_real_escape_string($con,$_POST['mi_busqueda']);
                $resultados = mysqli_query($con,"SELECT * FROM students WHERE 
                student_qr LIKE '%$mi_busqueda%'");
                while($consult = mysqli_fetch_array($resultados))
            {
        echo 
        '
            <tr >
                <td>'.$consult["student_group"].'</td>
                <td>'.$consult["student_name"]." " .$consult["student_secondname"]. " ". $consult["student_lastname"]. " ".'</td>
                <td>'.$consult["student_credits"].'</td>
                <td><button type="button" class="btn btn-warning" id= "show" onclick="show()" >Añadir Creditos</button></td>                    
            </tr>
            </div>
        </div>
    </div>
    ';
  } 
}

?> I tried doing an echo but I don't see results, I suppose that the data remains from the external query, I don't know how I could generate said query on the same page by calling the modal instead of sending the data with javascript through JSON