By opening Oracle in web browser, I am assuming you mean how to access Enterprise Manager via the browser which can be done using this URL construct – http://hostname:portnumber/em where host name is the name of the computer where you installed Oracle and port 5500 by default. Useful documentation can be found at http://docs.oracle.com/cd/B13789_01/server.101/b10742/em_manage.htm. The Max memory depends on the operating system type and version, but Oracle can scale to the Max of the machine and operating system. The IP address is the address of the machine you installed the Oracle server software on. I hope that this information helps.