mysql add an existing privileges for a user code example

Example 1: mysql update privileges

mysql> REVOKE ALL ON example_database.* FROM 'user_name'@'host_name'; 
mysql> GRANT privilege1, privilege2 ON example_database.* TO 'user_name'@'host_name';

Example 2: how to add privilege in mysql user

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