I want to form a chat bot

That's a start. You've picked what that app may do and the language but didn't share what is stopping you. If your intent was to find collaborators then you didn't state that.

Then we have other issues like what communication system is this going to use. Most I know today are on the web so C++ would not be my choice today. Maybe you are thinking about Eliza? Chat or chatterbot is found with https://www.google.com/search?q="eliza"+c%2B%2B