My project is to display the contents of a textbox created by vb2010 on 7 LED matrix 8x8 guided by Arduino and MAX7219
until now I managed to display a pre-text ECRI clicking a button in a form of vb
can you guys please help me
Help you in what?
What is pre-text ECRI?
You are a bit vague on the details.
However, if you want to send a string via serial interface to the Arduino and have it displayed on 8x8 matrix modules, then there is an example in the MD_MAX72xx or Parola librraies where a string from the Serial monitor is displayed. This could be adapted (or probably used as-is) in your application.