Add Category Title Above Content On Each Page(s)

this is a corresponding area from the default theme’s archive.php:

<?php /* If this is a category archive */ if (is_category()) { ?>
		<h2 class="pagetitle">Archive for the ‘<?php single_cat_title(); ?>’ Category</h2>

https://codex.www.ads-software.com/Template_Tags/single_cat_title
<?php single_cat_title(); ?> will echo the category title.

obviously, add this to category.php (or archive.php).

btw: the default theme is always a useful source of inspiration, to find out ‘how it is done’

Thanks but I don’t have a category.php file. From what I know of, copying the index.php file and calling it category.php is enough, right? And I do have an archive.php, but would thay show any changes in categories?

this might answer yuor question:
https://codex.www.ads-software.com/Template_Hierarchy