change user root privelige and password

Let me show you an example. I log in to the MySQL server as root the user using the command:

$ mysql -u root -p

Create a database user with a weak password:

mysql> create user 'ostechnix'@'localhost' identified by 'mypassword';

And I encounter the following error:

ERROR 1819 (HY000): Your password does not satisfy the current policy requirements