How to input text in unity by drawing rather than using keypad

Hello, i need help with the scenario below
i want to use a trail renderer to draw text and the text should be recognised as as letters. I am trying to avoid using keypad because it takes a lot of game space. So i want to draw letters. Any help with this?

So character recognition would probably require some sort of basic AI. There may be a Unity Asset on the store that could do this out of the box.