With it being a live cd there probably is not a password for root. You may already be root as well. Here are a few useful commands to know
This command tells you what user you are running as. for example if you are root, and execute whoami, it will return root. If you are bob and run whoami, it will return bob.
This command is used to change your password. Alternative root can change anyones password by running passwd username
This command stands for present Working Directory. As you may guess, it tells you where you are at in the file system.
This command stands for switch user. If you type su, it is assumed you are switching to the root account. Alternatively you can type su username to switch to another account. You must know the password of the account you are switching to.