Hello,
You can change the root password of your server with the command below.
sudo passwd root
The system will prompt you to enter your password – this is the same password you use to log in to the system.
Next, the system will prompt you to enter a new password. Do so, and then re-enter it exactly the same when the system prompts you to retype the password. This double-entry confirms that you have typed the password correctly.
Best Regards.
Cloud Turkey IT