Can u help me to select the right C++ code to control my robot?

My robot have 2 bipolar stepper motors, the first one will be directly connect to the Serializer and it will have to move CW and CCW with the same motor speed

For the other stepper motor  will connect to an external stepper controller (via the TTL serial port in the Serializer) and this motor should work also CW and CCW with the same motor speed

So plz tell me what are the codes that I should but in the VB commend. I develop the VB layout but don’t know what codes is should put inside each commend bottom. There are 4 bottoms (to allow the user to control the robot so the robot will go to the 4 directions up, down, right n left)

The big picture: when the user will click in the right arrow on the keyboard the robot will move to the right direction.

By the way Serializer that i use will interface using Bluetooth serial interfaces modules

All the best

Mema