Pagination and photo grid

[shdn]

Hi folk,

Related template: https://www.w3schools.com/w3css/tryit.asp?filename=tryw3css_templates_portfolio3&stacked=h 

When i click page 2, 3, 4...always display page 1

How can i set photo for page 2, 3, 4?

Code from this template:

<!-- Pagination -->
  <div class="w3-center w3-padding-32">
    <div class="w3-bar">
      <a href="#" class="w3-bar-item w3-button w3-hover-black">«</a>
      <a href="#" class="w3-bar-item w3-black w3-button">1</a>
      <a href="#" class="w3-bar-item w3-button w3-hover-black">2</a>
      <a href="#" class="w3-bar-item w3-button w3-hover-black">3</a>
      <a href="#" class="w3-bar-item w3-button w3-hover-black">4</a>
      <a href="#" class="w3-bar-item w3-button w3-hover-black">»</a>
    </div>
  </div>

Thank you