I worked on the normal stepper motor with 5V and worked out the enclosure for the rack and pinion mechanism for the motor and will be moving towards to the tiny stepper motor and building the box next week.
Struggles
I was working with the square motor driver but since it has too many wires to be attached to, I switched to the long ez motor driver with only dir and step since it has fewer wires to attach to.

Enclosure
I laser cutted the rack and pinion structure and made sure it is securely stabled as the enclosure below.

I got the cutest stepper motors. Yet the problems came to me: How should I fixate the rack and pinion structure onto the motor since it already has a rack? What ways should I create the structure for it? 3D print? Laser cut or more?

After chatting with Nicole, she recommended me to laser cut the rack and pinion structure as small as possible and see if it is doable first. If not, she would recommend me to take a look at the resin 3d printer.
I then went on laser cutting the mechanism and it worked!
Here is the video of me printing the smallest size of rack and pinion mechanism as possible.
Here is the rack and pinion structure that fits the small stepper motor I have.
