help with tags in custom template

Hello,
I’m creating a new theme and everything seems to work well. I understand that when the home is loaded, wordpress reads home.php. When a category is displayed, wordpress reads category-#.php.
I have tags associated to the news. This tags are displayed under the content of the new, while reading single.php (using <?php the_tags( ‘<hr><p>Tags: ‘, ‘, ‘, ‘</p>’); ?>)

Now, the problem is when I click one of these tags, I don’t know what file is used as template to show all the posts under this tag.

Could anyone help me with this?
Thankyou