took a look and there is not way I will understand where to put the code with dev tools

but found it in PHP anyway.
so here it goes in case someone is looking for the same thing
head.php
look for: <?php echo osc_category_name() ; ?></a></li>
and change it to: <?php echo osc_category_name() ; ?> [<?php echo osc_category_total_items() ; ?>]</a></li>
will re post it as {HOW TO]
thank u guys!
What about showing the total of subcategories in the whole site?
<?php echo osc_total_subcategories() ; ?> ?