The answer is yes to both of your questions.
The web interface is automatically included in Splunk, by default it's available at http://hostname:8000
Most modern browsers will do, full list here: http://docs.splunk.com/Documentation/Splunk/6.0.2/Installation/Systemrequirements#Supported_browsers
I got "http://hostname:8000" after installing and starting splunk. But what I mean is the whole windows with browser where I can put this "http://hostname:8000" to access. How can I get it? Or is there any command to open this window.?
Thanks