clownzassieq
You can render these extra fields by editing the layout of article page:
root/templates/ja_spa/html/com_content/article/
Edit the php file associated with the article layout you're using.
Under line: defined('_JEXEC') or die;
add this:
use Joomla\Registry\Registry;
// Get Custom Field
$extrafields = new Registry($this->item->attribs);
$duration = $extrafields->get('duration');
$priceBase = $extrafields->get('price-base');
$priceSale = $extrafields->get('price-sale');
Then put this code to the place you want to show these extra fields:
<?php if($duration || $priceBase || $priceSale) :?>
<div class="wrap-extrafield">
<div class="row">
<?php if($duration) :?>
<div class="col-12 col-sm-6">
<div class="ext-title">
<?php echo Text::_('TPL_DURATION') ;?>
</div>
<div class="ext-content">
<?php echo $duration ;?>
</div>
</div>
<?php endif ;?>
<?php if($priceBase || $priceSale) :?>
<div class="col-12 col-sm-6">
<div class="ext-title">
<?php echo Text::_('TPL_PRICE') ;?>
</div>
<div class="ext-content">
<?php if($priceSale) :?>
<?php echo $priceSale ;?>
<span class="price-old"><?php echo $priceBase ;?></span>
<?php else : ?>
<?php echo $priceBase ;?>
<?php endif ;?>
</div>
</div>
<?php endif ;?>
</div>
</div>
<?php endif ;?>
and customize style as you wish.