can clock to control a stepper motor ?

A good way to generate an accurate frequency to control a stepper motor is with a crystal oscillator and a frequency divider.

One rotation for a stepper motor requires a large number of step commands. The number depends on the stepper motor and is clearly stated in the data sheet for the stepper motor. Assuming you have a stepper motor that rotates 3 degrees per step, one rotation will require 120 steps, which for 1 RPM is 2 steps per second. Each step command is usually divided into four phases of equal duration, so you will need a clock frequency of 8 Hz.

You can get 8 Hz from a CD4060 using a 32.768 kHz watch crystal. Google those keywords and you'll find a circuit. If you need some other frequency, you can change the division ratio of the CD4060, with some limitations.

You will then need a stepper motor controller that can generate the necessary phases in the right sequence, or you can use a circuit made from flip-flops. You'll need a driver that will provide the required current to the stepper motor. These subjects are covered on many web sites, and Googling those keywords will get you started.

You may find it better to run the stepper motor at a higher speed than 1 RPM and gear it down, to avoid the little jumps that occur on each step.

This whole issue has already been discussed on another thread:
https://www.electronicspoint.com/help-small-project-precise-1rpm-motor-and-circut-t256056.html

You might want to compare notes with the guy who started that thread.

 

As I recall, a very similar project, but for a professional telescope, is showcased in "The Art Of Electronics" with all considerations discussed.

 

That is discussed in the other thread. I don't think a DC motor would be accurate enough.

 

The professionals who wrote the book I mentioned used a simple phase-locked loop design (and installed it at Mauna Loa if I remember correctly).
The PLL drove a stepper motor.