Welcome @virendrarajpurohit . You can read contributing guidelines and find projects here: https://docs.plone.org/develop/index.html12. You can find issues for beginners at https://github.com/plone/Products.CMFPlone2
@virendrarajpurohit We do have a lot of activity in our Volto (Plone React) project and Pastanaga UI. You can see them in these repos https://github.com/plone/volto and https://github.com/plone/pastanaga so you should try to get familiar with them, and with Plone itself. If you haven't already, please see Plone.org/gsoc6 for more hints (from 2018) on how to get started.