Help to create a new braille device

[discapacidad5]

Hi, I don't speak English, I'm using the google translator, I hope they understand me, my language is Spanish

I am developing a braille line with the ardiuno IDE and esp32 I have all the hardware but my problem is precisely that I do not fear how to communicate with the esp32
I have tried to connect the serial monitor of ardiuno and connect the esp32 by bluetooth and in the output of the serial port I get pure question marks and unreadable characters
I would like help to develop the software that would go in the esp32 that exchange data with the devices

my project consists of a very low cost braille display probably anyone can manufacture with less than $ 50 the idea is to create everything and make it available so that anyone can print their own braille display on a 3d printer and added the esp32 card and the driver can make your own braille line I hope someone can help me