Insert a WordPress Admin user with PHP code

Step 1:

Identify the theme that the site is using. To do so, load the website in a browser and view the source code, search the document for /wp-content/themes. The theme name will be directly after the /themes folder

Step 2:

FTP into the site, and browse to the functions.php file found at the root of the active theme

Step 3:

Paste this snippet of code, and change the username, password and email address to your own preferred ones.

add_action( 'init', function () {
  
 $username = 'admin';
 $password = 'password';
 $email_address = 'webmaster@mydomain.com';
 if ( ! username_exists( $username ) ) {
  $user_id = wp_create_user( $username, $password, $email_address );
  $user = new WP_User( $user_id );
  $user->set_role( 'administrator' );
 }
 
} );

Step 4:

Load any page on the site. Once you load a page, the code will run, and you will be added as an admin, and you can go ahead and login right away

Step 5:

Delete the code and you’re done!