Arduino + Stepper Motor + Rotary Encoder + LEDMatrix

Stepper motor NEMA17 driven by driver TB6600 (12V source) should rotate endlessly at a certain speed. The speed should be determined / controlled by a combination of a Rotary Encoder and a MAX7219 (8x8 LED matrix, driver included) > Each rotation click of the rotary encoder lights an LED on the matrix, one by one, in order, until the matrix is full. Depending on the direction of rotation, you can add or substract lighted LEDs on the matrix. The number of alight LEDs represent the percent of the maximum speed of the stepper NEMA 17. There are 64 LEDs on the matrix, representing 100% of a predetermined speed when all lit. Rotary button press starts the motor rotation. So, rotate the encoder (forward or backwards) to determine the speed, which will be reflected in number of lit LEDs on a LED matrix, then press encoder to start the rotation of the motor. This is the project. If possible, after the start of the rotation, to be able to still modify the speed (as described above) and apply it by pressing the encoder button a second time. I suppose that one might use libraries like Rotary, LedControl, AccelStepper. I tried, found similar projects for parts of it, but as I'm not a programmer, I didn't succeed to compile them in one single project.