USING CUSTOM THEME
Go to /app/vendor/magento/module-catalog/view/frontend/templates/product/view/
Copy the file attributes.phtml into you custom theme under the following directory
Magento_Catalog\templates\product\view
Now change the file according to your needs, here is an example :)
<?php
$_helper = $this->helper(Magento\Catalog\Helper\Output::class);
$_product = $block->getProduct();
?>
<?php if ($_additional = $block->getAdditionalData()) :?>
<div class="additional-attributes-wrapper table-wrapper">
<table class="data table additional-attributes" id="product-attribute-specs-table">
<caption class="table-caption"><?= $block->escapeHtml(__('More Information')) ?></caption>
<tbody>
<?php foreach ($_additional as $_data) :?>
<tr>
<th class="col label" scope="row"><?= $block->escapeHtml($_data['label']) ?></th>
<td class="col data" data-th="<?= $block->escapeHtmlAttr($_data['label']) ?>"><?= /* @noEscape */ $_helper->productAttribute($_product, $_data['value'], $_data['code']) ?></td>
</tr>
<?php endforeach; ?>
</tbody>
</table>
</div>
<?php endif;?>
<?= 'HELLO WORLD' ?>
USING CUSTOM MODULE
Copy the file:
app\code\magento\vendor\magento\module-catalog\view\frontend\layout\catalog_product_view.xml
into
app\code\vendor\module\view\frontend\layout\
changereplace the line:
<block class="Magento\Catalog\Block\Product\View\Attributes" name="product.attributes" as="additional" template="Magento_Catalog::product/view/attributes.phtml" group="detailed_info">
towith
<block class="Magento\Catalog\Block\Product\View\Attributes" name="product.attributes" as="additional" template="Vendor_Module::product/view/attributes.phtml" group="detailed_info">
Copy
/app/vendor/magento/module-catalog/view/frontend/templates/product/view/attributes.phtml
to
app\code\vendor\module\view\frontend\templates\product\view\