Own taxonomy category overview template

Hi together,

I have an WordPress template that is giving me my own WordPress taxonomies category overview (it shows all categories):

$args = array(
    'taxonomy'     => $taxonomy,
    'depth'        => $depth,
    'orderby'      => $orderby,
    'show_count'   => $show_count,
    'pad_counts'   => $pad_counts,
    'hierarchical' => $hierarchical,
    'title_li'     => $title
);

$categories   = get_categories($args);

And then I show:

foreach ($categories as $category) { // bla bla }
Everything is fine. But now I want to do this: On click on the category name it shall open “mywp.com/taxonomy-overview/taxonomy-1” and show all taxonomy items.

How can I add this functionality into my taxonomy-cat.php template? First, I have to make an URL with the ID of the portfolio

$url = get_permalink( $post->ID ).$category->term_id;

This gives me /taxonomy-overview/1 but if I click on it, I get a 404. How can I tell my WordPress, that it should call a new template file, e.g. “taxonomy-list.php”? And how do I fetch the Taxonomy ID from the URL? And how do I make the “SEO” (mod_rewrite) URL on my -cat.php template?

Edit: my taxonomy-cat.php is a page layout so it’s assigned to a page…