error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near

Try this:

CREATE USER 'wordpressuser'@'localhost' IDENTIFIED BY 'password';

Remember the quote in used is not around the @ symbol, and it is not ‘ ’ but ' '. And the first thing to do is to provide the user with access to the information this wordpressuser will need.

GRANT ALL PRIVILEGES ON * . * TO 'wordpressuser'@'localhost';

The asterisks in this command refer to the database and table (respectively) that they can access—this specific command allows to the user to read, edit, execute and perform all tasks across all the databases and tables.

Once you have finalized the permissions that you want to set up for your new wordpressuser, always be sure to reload all the privileges.

FLUSH PRIVILEGES;