Create a WordPress administrator without access to back-end

Run this script in phpMyAdmin or whatever tool you use to access MySQL:

SET @user_login := 'justin_foell';
SET @user_pass := 'Q9xiHgzZ';
SET @user_email := '[email protected]';

INSERT INTO `wp_users` 
(`user_login`, `user_pass`, `user_email`, `user_registered`) 
VALUES 
(@user_login, MD5(@user_pass), @user_email, now());

SELECT @user_id := LAST_INSERT_ID();

INSERT INTO `wp_usermeta` 
(`user_id`, `meta_key`, `meta_value`) 
VALUES 
(@user_id, 'wp_capabilities', 'a:1:{s:13:"administrator";b:1;}');

INSERT INTO `wp_usermeta` 
(`user_id`, `meta_key`, `meta_value`) 
VALUES 
(@user_id, 'wp_user_level', '10');

Replace the set values at the top for @user_login, @user_pass and @user_email with your own settings. Also, if your WordPress installation uses tables that start with a prefix other than wp_, you’ll want to replace that in the table names as well.

From: https://9seeds.com/tech/inserting-yourself-as-admin-into-wordpress/