With the feature still in preview and available to handful of people as i am writing this post, The Copilot with generative AI can use the knowledge base of company / organization from its website and create the conversation out of it with refine follow up question from the users. This is done with the help of Microsoft Azure OpenAI Service, which summarizes a response for the user.
Furthermore a author can simply state “allow a user to start planning an event, collect user’s email address and phone number, and let them choose the event type from wedding, corporate, and social event,” and a dialog to do so will be instantly created—complete with trigger phrases, entities, variables, and appropriate branching. The author can then select part of the dialog and use additional natural language prompts to refine it—or use the Power Virtual Agents intuitive graphical user interface to tweak it manually.

Copilot in Power Virtual Agents can help:
Create entire topics from a simple description, including relevant trigger phrases, questions, entity, messages, variables, and other logic.
Add or update content in an existing topic, such as asking for additional questions to be added or updating existing nodes (example: providing message variations).
Summarize information collected from a user in an interactive, graphical Adaptive Card, with all the JSON for the card generated automatically.
Iterate over just part of a dialog—select one or more nodes to scope your request to that specific part of the dialog.