Hi,
I am looking for a 4 stepper motor controller for Arduino(Mega) I need to rune a robot car
Mthulisi
If by “4 stepper motor” you mean 4 separate motors and not just one motor with 4 wires, the use of a RAMPS board could benefit you. Buy one of those and place four stepper motor drivers such as the drv8825 or the a4988 in the board and then use the arduino to control the four separate motors.
For the purpose of a robot car, however, large stepper motors arent really needed. The use of a 28BYJ-48 stepper motor is easier and well sufficient if you plan to have one per wheel. To use this, get the (sometimes) included ULN2003 driver for it. See here as an example -> https://www.instructables.com/id/BYJ48-Stepper-Motor/
There are other options but im sure those will get you off the ground. Dont hesitate to ask if you want to know them.
Hope that helps!
That’s some solid advice @Abram68481
I managed to fit this into the live video yesterday and can also recommend the DRV8824. Though these little modules are not as featured as a full RAMPS board. They are still worth checking out and keeping handy for stepper motor projects.
As always, lots of ways to go about things 
