RE: Is there any way to make bot send a pdf file to Telegram group ?

Responses in Bot Libre are HTML and can include <img> <video> and other tags. When Bot Libre sends a message to social media it translates the HTML it to whatever artifacts the social media platform supports.

For Telegram your bot can include an image in a response using the <img> tag. For the img src you can upload the image to Bot Libre from the response editor in the Training & Chat Logs page.

For including a file in a response, the best way is to link its URL. You can upload the file to Bot Libre from the response editor in the Training & Chat Logs page.