How to go to another page.php with condition

The logics of this sample will guide you to solve your problem. Linking to your download page will involve the same programming logics as this sample. You may try something like:

<?php
if(isset($_REQUEST['sign'])){
   if($_REQUEST['sign'] == 'signup'){
//This redirects the user to the Signup page
      header("Location: /page0.php");
//When the user is redirected to this page you present to them a login form. Upon login you verify and validate their information, and when satisfactory, you use the header function to redirect them to your download page. The same logic will be applied in the signup form.
   }
   elseif($_REQUEST['sign'] == 'signin'){
//This redirects the user to the Login/Sign in page
      header("Location: /page1.php");
   }
}
?>;

Hope this works for you, and helps you solve your problem.
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