How to Change A User's Password in Linux
1) SSH to your server
2) run the following command:
3) Enter your new password. Ensure there are no typos - copy and paste from a temporary notepad file is good practice but ensure you delete the file afterwards as you don’t want to leave passwords laying around in plain text.
4) Enter the password a second time.
You have now updated your password. As a root user you can update the passwords for other users aside from just root if required by your colleagues.