Hi Miltos,
The "Book now.." button there is for the demo purpose only, there is no link there yet by default.
You can edit this file: ROOT/templates/ja_trip/html/com_content/article/tour.php
look for this code:
<a class="btn btn-primary w-100" href="#" title="Book Now">Book Now for <?php echo $price; ?></a>
and add your own link to the href
param
Regards