PHP - Problem Inputting Data That Has A Single Quote

<?php
$res1 = preg_match('/shi*t/', $comment);
$res2 = preg_match("/shi*t/", $comment);
?>

   $blog= mysqli_real_escape_string($con, $_POST['blog']);
   

        $blog= $_POST['message'];
            
        $sql = "SELECT * FROM table WHERE `message` = '{$message}'";
        
        $result = mysql_query($sql);
        
        if ( mysql_num_rows ( $result ) > 0 )
        {
                        
            $error = "Message Exists.";
        }
        
        else
        {
        
         $error = "This message does not exist. Insert it!!!";
        
         $sql="INSERT INTO table (message) VALUES ('$_POST[message])";
        
        
        }
        
        if (!mysqli_query($con,$sql))
         {
         die('Error: ' . mysqli_error($con));
         }
        
        mysqli_close($con)

This is the second script I’ve installed on the same site and admin has been able to delete from the database, but somehow still can’t insert into database? My config is set right, but can’t understand why two different scripts are having the same issue?

if(isset($_POST['submit']) && ($_POST['vendor']!='') && ($_POST['item']!=''))
{
$sql="SELECT supplier.id AS sid, supplier.name AS SNAME, supplier.category, supplier.website, supplier.email, supplier.phone, supplier.vat, supplier.pan, supplier_location.id, supplier_location.supplier_id, supplier_location.location, supplier_products.id, supplier_products.supplier_id, supplier_products.product_id, location.loc_id, location.name AS locname, products.product_id, products.name AS pname FROM supplier INNER JOIN supplier_location ON supplier.id = supplier_location.supplier_id INNER JOIN supplier_products ON supplier.id=supplier_products.supplier_id INNER JOIN location ON supplier_location.location = location.loc_id INNER JOIN products ON supplier_products.product_id=products.product_id WHERE supplier.id=".$sup." AND supplier_products.product_id=".$product;
$sql1 = mysql_query($sql) or die(mysql_error());


<table>
<thead><tr>
<th>Vendor ID</th>
<th>Vendor</th>
<th>Category</th>
<th>Website</th>

<th>Email</th> 

<th>Phone</th>
<th>Products</th>
<th>Locations</th>
 <th>VAT</th>
  <th>PAN</th>
                        
                       
                        


</tr>


</thead>
<tbody> 


<tr>
<?php
while($row = mysql_fetch_array($sql1))
{ 


?>
   
   
    <td><?php echo $row['sid'] ?></td>
<td><?php echo $row['SNAME'] ?></td>
    <td><?php echo $row['category'] ?></td>
    <td><?php echo $row['website'] ?></td>
     <td><?php echo $row['email'] ?></td>
    <td><?php echo $row['phone'] ?></td>
    <td><?php echo $row['iname']; ?></td>


    <td><?php echo $row['locname']; ?></td>


    <td><?php echo $row['vat'] ?></td>
    <td><?php echo $row['pan'] ?></td>




</tr>


<?php 




}
?>
</tbody></table>


}

I have a navigation list displaying which is a mix of html and php, everything is working fine however now I want to convert this block of code into a function but am having major problems with quotes.

The line of code I currently have is 

$data = $db->query("SELECT * FROM menu")->fetchAll(PDO::FETCH_ASSOC);

foreach ($data as $row) { ?>
     <li><a href="<?php echo $row['url']; ?>" title="<?php echo $row['title']; ?>"><?php echo $row['icon'] . ' ' . $row['header']; ?></a></li>

<?php
	}
?>

As I say everything works using the above but now I am trying to echo the full li out and am having major issues with single and double quotes.

I currently have 

echo "<li><a href='#' title='the title'><i class='fas fa-user site-nav--icon'></i> Help</a></li>";

Now I am trying to use the $row['url'], $row['title'], $row['icon'] & $row['header'] as per the top example but I cannot get the combination of quote marks correct, whether to use double, single or a combination.

I would be grateful if someone could suggest the correct syntax for the a tag then I can work through the rest.

Thanks

PHP script return 20 UL LIST values like,

< ul >

A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T

< /ul >

How to display UL LIST into row wise 5 columns like

A B C D
E F G H
I J K L
M N O P
Q R S T (20 ITEMS)