Basic gallery with PHP JavaScript and MySQL

I want to create a page which shows e.g. 10 pictures/posts and when you click the next button the next 10 pictures/posts should be added to the page. So when the page loads it should display 10 pictures/posts when you click "next" then the pages shows 20 pictures/posts and so on.

Until now I store the pictures in a folder and their filenames are stored in a table of my database. The posts are also stored in a table of my database.

So I select all posts and picture names from my database and then I create an array with them.

Next I display every row of the array with a while loop.

So what should I do to reach my goal which I described at the start preferably using PHP, HTML, CSS, MySQL, JavaScript?

$res = mysqli_query($conn, "SELECT * FROM entries INNER JOIN users ON entries.userid=users.userid ORDER BY date DESC");

while($dsatz = mysqli_fetch_assoc($res))
{
    $id = $dsatz["entriesid"];
    $title = $dsatz["title"];
    $title = str_replace("\n","<br>",$title);
    $entry = $dsatz["entry"];
    $entry = str_replace("\n","<br>",$entry);
    $date = $dsatz["date"];
    $picture = $dsatz["picture"];
    $user = $dsatz["name"];
    $user = str_replace("\n","<br>",$user);

    echo  "\n\n<div id='post'>"
        . "<h4>$title</h4>"
        . "<div>$entry</div><br />"
        . "<div><img src='$picture' alt=''/></div>"
        . "<div>Author: $user</p></div>"
        . "<div><em>" . date("$date") . "</em></div>"
        . "</div>";
}