Greetings, @aditodkar! Thanks for expressing interest in GSoC with Plone. We'd love to have your help in making the Patterns-based Widgets in Plone better. I encourage to to begin by reading this post to get yourself started learning about Plone. There are certainly issues in the linked list of beginner-friendly issues that you could work on given your skills.
As for what you would need to begin contributing to Patterns? I will let @seanupton give some more feedback on that, but I don't think you need specific jQuery knowledge, and I'm certain you do not need to know AngularJS to contribute there. If you have some reasonable JavaScript knowledge, that should be enough to get started. It's our job as mentors to help point you to the things you'll need to learn.
Again, welcome to Plone. We are glad you're here.
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