You can dictate messages to your iPad to be automatically typed out. To do this, tap the microphone key (if the key isn’t visible enable Siri from Settings > Siri & Search) next to the space bar and start speaking. Once finished, just tap Done.
To include punctuation, just speak it. For example, for the sentence “Hey, how are you today?” you would say, “Hey comma how are you today question mark.” You can even add paragraphs by saying, “new paragraph.”