Text message auto reply Merged

Hello. I am trying to determine how to create an auto reply to incoming text messages such as “not authorized” and to email my official email address instead of texting informally. I do not want to completely disable incoming text messages because some carriers do not let their users know that the text message they were attempting to send did not go through. I just want the ability to auto reply with instructions on which email address to formally send correspondence because I do not authorize correspondence via text messages.