@gilbert basing on the logs, you are creating an SDK instance and the error you are getting is because you entered a wrong password to the the root. The root password is the one you created while installing Mysql on your machine. Besides that, where the is an option of default just press enter. The demo server can be accessed on this https://openmrs.org/demo/ link.
@gilbert just incase you forgot your
root password you can access it through the runtime properties file by following this path
On Windows systems:
C:\Documents and Settings\YOURUSERNAME\Application Data\OpenMRS C:\Windows\system32\config\systemprofile\Application Data\OpenMRS
On Mac OS X or Linux systems: