Kamal, it might be somewhat difficult at the beginning, but with the time you'll get used to it. There are several ways to display the content in the Studio: one is in the Systems tab, under Content you should see (among others) sap, when you open it, there is hana and further on democontent and epm. Another possibility is to go through the Repositories tab in the Development perspective. As to the demos themselves, this might be even more tricky - the URL is http://<hana_server_address>:<port>/<package>/<project>/<path inside project>. <port> is said to be 8000 + instance number, however on our Hana this is plain 80. So to access the launchpad, I use http://NN.NN.NN.NN/sap/hana/democontent/epm/ui/launchpad.html. Another possibility look at the demo stuff is using the IDE editor directly from the browser, this is in http://<hana_server_address>:port/sap/hana/xs/ide/editor.
As to the native examples themselves - those in the Developer Guide pdf's are quite trivial or they do not explain a lot of the UI making. The developer guide in https://sapui5.hana.ondemand.com/sdk/docs/guide/95d113be50ae40d5b0b562b84d715227.html is better, however not all its examples are working, I'm currently stuck at the very first one (Best practice).
-- Micha