The recommended way to recreate the footer to original would be to temporarily switch to one of the default WordPress themes, delete Azuma and then re-install and active Azuma.
Then if you need to edit or remove part of the footer.php file, it is recommended to do this in a child theme so that your changes are not undone when the theme is updated.
You can copy footer.php file to the child theme and it will override footer.php from the parent theme.
Or alternatively you can leave footer.php intact and override the azuma_powered_by() function in the functions.php file of the child theme as this is where the link to WordPress is located.
Whichever way you do it, the most important part of the footer NOT to remove is the wp_footer() function as this is needed by WordPress for your site to function correctly.