battle.html

<!DOCTYPE html>
<html lang="en">
  
  <head>
    <meta charset="utf-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1">

    <title>Hello!</title>
    
    <!-- import the webpage's stylesheet -->
    <link rel="stylesheet" href="style.css">
    <link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Press+Start+2P">

    <!-- import p5 things -->
    <script src="https://cdnjs.cloudflare.com/ajax/libs/p5.js/1.0.0/p5.min.js"></script>
    <script src="https://cdn.JsDelivr.net/gh/bmoren/p5.collide2D/p5.collide2d.min.js"></script>

    <!-- import the webpage's javascript file -->
    <script src="scripts/battle.js" defer></script>
    
  </head>  
  <body>
    <div id="p5_loading" class="loadingclass">
      Loading...
    </div>
  </body>
</html>