Hi @pavithirakc - welcome to Plone and thank you for your interest!
GSOC student applications will open on March 20.
@ebrehault had a nice answer in Gitter re: how to get started with the progressive web app:
first thing to do for you is probably to install Plone + plone.restapi
so checkout https://github.com/plone/plone.restapi
then set up a Python virtualenv
bin/buildout -Nv -c plone-5.0.x.cfg
and you will get a Plone instance with restapi
create a basic Plone site with few random contents
and start from here
As @cewing wrote, "A terrific first step to learning more about Plone will be to select one of the issues marked for beginners in our issue tracker in github. Working on fixing something small, or writing some documentation, is a great way to get started understanding how Plone works underneath. You can learn how to contribute to Plone in our documentation."