You create individual MySQL accounts from your cPanel control panel. All of these will be prepended with your account username, so if you set up the database and username of dbase, you would enter yourusername_dbname into the software setup.
The database host is always localhost, and the port number should be left as default.

To create databases, log into your control panel [ http://www.mydomain.com:2082 ] and select MySQL Management under Your Account. Click Create new Database and fill out the form.