Mysql Change root password

 go to command line and

sudo mysql -u root

 use mysql;

select Host, User,authentication_string, plugin  from user;

UPDATE mysql.user plugin='mysql_native_password' WHERE User='root' AND Host='localhost';
 

ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY 'set you password here';
 

flush privileges;
 

Putty key format too new