
Welcome to Microsoft Q&A! Thanks for posting the question.
You can refer to Power Virtual agents with Azure OpenAI documentation to understand how you can connect PVA to an Azure Open AI resource on your data. Additionally, you can refer to Use content on SharePoint or OneDrive for Business for generative answers on details to fetch SharePoint contents for the bot, however, please note that due to memory limitations you may have to limit the size of the files you want to use on SharePoint. You may need to consider splitting the file into smaller sized ones.
Hope this helps to get you started on.
Please let me know if you have any questions.
Thanks
Saurabh
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