Accessing OneDrive through MS teams using Microsoft Graph API

Hi
I want to access my OneDrive Files using a custom chatbot inside MS Teams chat with the help of MS Graph APIs. I want to download those files using this chatbot when I provide a URL of the file. 

EG: if the the file URL is https:/my.sharepoint.com/xyz , then my command to the chatbot should be like "@chatbot download https:/my.sharepoint.com/xyz" and the file should be downloaded inside MS teams.

Please suggest a detailed solution if available.