Make a bot that can target application/website users and send them a message.

I need a bot that will automatically send message to all the users of certain application and or website. These applications/website can be social like Instagram, Facebook or utilities. Bot capabilities: Upon entering the name of the application or website, it checks IF the application/website have in app messaging system, if it does, then it just send the desired message to all the users of that app/website like Instagram, Facebook e.t.c IF the app/website doesn't have in app messaging system, it pulls user information like email address/phone number... from the website/application database and send them a desired message. Please read and understand what I want before bidding. Present me with a demo or something like that that you did or know.