I am a novice to web-sphere application server.
I am not able to figure out where I can get the url of application installed and what is default port number used for http requests.
Any help will be appreciated.
The port numbers used can be specific to you particular WAS installation and depends on the topology as well. You can either try default 9080 or look for the port number in WAS configuration. What you're looking for is WC_defaulthost for http and WC_defaulthost_secure for https.
If you have access to WAS admin console, navigate to Servers => WebSphere Application Servers and choose your server. Then look for Communication sections which contains Ports.
Of course it is always possible to look for the port number on disk. For example:
<WAS_HOME>/profiles/<PROFILE_NAME>/logs/AboutThisProfile.txt is generated when creating the profile, so contains the port numbers as well. Then you can take a look at <WAS_HOME>/profiles/<PROFILE_NAME>/config/cells/<CELL_NAME>/nodes/<NODE_NAME>/serverindex.xml