Do I just set the pin it’s connected to to high then turn it to low again so many ms later?
Unless you only want your stepper motor to go in one direction, you are going to need at least two pins to control our A4983 stepper motor driver carrier. Those two pins would be connected to DIR and STEP. Remember also that NOT RESET is floating on the carrier that does not have voltage regulators.
The way you describe the driver responding to a pulse (on STEP?) sounds reversed. From page 7 of the datasheet,
Check out the datasheet on the Resources tab of the product page for more details about how to control the driver.