$ wget https://ja.wordpress.org/latest-ja.zip
$ unzip latest-ja.zip
$ sudo cp -r ~/wordpress /var/www/html/

$ mysql -u root -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 9
Server version: 5.7.22-0ubuntu0.16.04.1 (Ubuntu)
 
Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
 
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
 
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
 
mysql> create database wpdb;
Query OK, 1 row affected (0.00 sec)
 
mysql> grant all on wpdb.* to 'wpadmin'@'localhost' identified by 'ここに平文のパスワード文字列';
Query OK, 0 rows affected, 1 warning (0.10 sec)
 
mysql> exit
Bye

http://__FQDN___/woprdpress/wp-login.phpにアクセス