Hi Kiran Budhia - It does not look like there is a way to auto-populate content in a newly created document in Jive X. There is an idea in the Ideas for Jive place around a feature request that matches what you're looking for - Bring QuickTemplates v2 Plugin to the Core Jive Product. I'd suggest adding your vote here to make sure this request continues to get visibility. Our product managers use these ideas when planning features to include in upcoming versions of Jive.
Let me know if this helps.