Pagination of php pages

I am creating a search system and I need to create a pagination I thought I would use $_SESSION but I noticed that it would give error follow below the code that I have developed so far

Search:

<?php
if(isset($_GET['PG'])){
    if(isset($_SESSION['pg'])){

        $id=$numpg-$_SESSION['pg'];

    }else{
        $_GET['PG']=0;
    }
}else{
    $_GET['PG']=0;
}
if(is_numeric($_GET['PG'])){
?>
<div class="corpo container">
<?php
$i=0;
?>
<div class="row">
<?php
    $ps=$_GET['PS'];
    $sql="SELECT id FROM indexes WHERE (modo!=4 and nome LIKE '%$ps%') ORDER BY id DESC";
    $exe=mysqli_query($link,$sql);
    $numrow=mysqli_num_rows($exe);
    if($_GET['PG']==0){
        $sql="SELECT nome,foto,vew,tkm,modo,id FROM indexes WHERE (modo!=4 and nome LIKE '%$ps%') ORDER BY id DESC LIMIT 12";
    }else{
        $sql="SELECT nome,foto,vew,tkm,modo,id FROM indexes WHERE (modo!=4 and nome LIKE '%$ps%') and (id <= $id) ORDER BY id DESC LIMIT 12";
    }
    $exe=mysqli_query($link,$sql);
    //echo e($numrow);
    while($row=MYSQLI_FETCH_ARRAY($exe)){
        $nome=$row['nome'];
        $foto=$row['foto'];
        $vew=$row['vew'];
        $tkm=$row['tkm'];
        $modo=$row['modo'];
        $pxid= $row['id'];

        $i++;

?>




<div class="col-md-3 sb-preview text-center">
<div class="card h-100">
<div id="vew">
<span class="glyphicon glyphicon-eye-open"></span>: <?php echo e($vew); ?>
</div>
<a class="sb-preview-img" href="<?php ?>">
<img class="card-img-top" src="../_img/<?php echo e($foto) ?>"    style="width:100%;">
</a>

<div class="card-body">

<h3 class="card-title">
<?php echo e($nome) ?> 
<?php if($modo == 1){ ?> 
    <span class="glyphicon glyphicon-film"></span>
<?php }else if($modo == 2){?>
    <span class="glyphicon glyphicon-camera"></span>
<?php }else{ ?>
    <span class="glyphicon glyphicon-header"></span>
<?php } ?>
</h3>
</div>
</div>
</div>



<?php
if($i==4){
?>
</div>
<?php
$i=0;
?>
<div class="row">

<?php
}
if($numrow>12){
 $_SESSION['pg']=$pxid;
}
}
?>
<?php
if($numrow>12){
    if($i>0 and $i<4 ){
      ?>  
      </div>
      <?php
    }
?>

<div class="row">
<nav class="text-center">
  <ul class="pagination pagination-sm">
  <?php
    $pg=$numrow/12;
    $pg = ceil($pg);
    //echo $pg;
    for($i=1;$pg>=$i;$i++){
    if($i==1){
  ?>
    <li><a href="?PS=<?php echo e($_GET['PS']) ?>&PG=0">1</a></li>
    <?php
    }else{
    ?>
    <li><a href="?PS=<?php echo e($_GET['PS']) ?>&PG=<?php echo e($i)?>"><?php echo e($i)?></a></li>    
    <?php
    }
    }
    ?>
  </ul>
</nav>
</div>
<?php 
}
?>
</div>
<?php

}else{

}
?>