For some reason you might want to change your password root through pa panel not through the VPS terminal, usually you change it via ssh terminal with the command:
Here Tinohost will guide you to change root password through Tino panel
Change root password on Tino Panel
First, visit the service management page at: https://my.tino.org/clientarea.php?action=services
Click to access the VPS service management panel you want to change the hostname of.
You click on change password to change the root password
Enter the new root password and click change password to confirm the change.
Finally, you restart VPS by Stop and Start VPS.
Start VPS again:
So you have successfully changed the root password via Tino panel, now you can access VPS with the root user with the password you just set.