Stepper Motor to work like a DC

Yes it cn be like A axis, or it can be exactly A axis as that makes it possible to control from gcode.
And yes, it will also work to stop from a sensor, although having full positional control makes using a switch redundant.

Is this for an existing machine with LinuxCNC control or just the axis alone?
For the latter, a simple pulse generator will do just fine, even an old transformer can make 50 or 60Hz pulses on it's own that can be used to run a stepper.
Small transformers are cheap and can be found on old radios/casette players/power adapters, etc. Use 2 resistors to bring the AC voltage to under 5V and wire it through the sensor to step pins on the drive.
Might be slow though...
Edit
Add a diode to prevent reverse polarity on input.

BonoCNC wrote:

To implement in a small Linux machine I built. I am doing some tests in my free time. I am a rockie, but very interested in learning more!

In that case, go with LinuxCNC for sure, it is magnificent once you get into it, and you can control stuff as you want, whatever that may be.
Forget what i said above about transformers n stuff!