How can i change url structure of cpt like this?

If I understand your question correctly, you can do the following:

• Identify the template being used to output your custom posts (or create one)
• Within this template, intercept the $_GET variable for date, sanitise it and parse it into a date that you can use in your posts query.
• Query the items (if you’re using the post date for date, you can use that; otherwise you can use a meta query to query on a meta value if you’re doing it that way).

Along the lines of

$day = date('d',strtotime($_GET['date']));
$month = date('m',strtotime($_GET['date']));
$year = date('Y',strtotime($_GET['date']));
$args = array(
  'posts_per_page' => -1,
  'year' => $year,
  'monthnum' => $month,
  'day' => $day,
  'post_type' => my_post_type,
  'order' => 'ASC',
  'orderby' => 'post_date',
  );
$myitems = get_posts($args);