Download grbl latest zip file from the github link https://github.com/gnea/grbl. Extract the zip file.
Now go to the \grbl-master\grbl folder and look for config.h file and open this file in any text editor and find the text for #define BAUD_RATE 115200 and replace 115200 to 9600. Now save the config.h and close the file. Zip the grbl folder inside the root grbl folder.
Now open arduino and click on Sketch menu and go to Include Library->Add .ZIP Library... and select the zip file of grbl
Now click on open and grbl firmware will be installed , After successfully installed the grbl folder will be created inside the library folder of Arduino Ide. Now open the grblupload.ino file from library folder. You will find the grblupload file in Arduino\libraries\grbl\examples\grblUpload path. After opening grblUpload file you see only this type
Don't worry just connect Arduino Uno using serial port and upload this file to the Arduino Uno.
Now we need CNC shield, Nema 17 stepper motor, AR498 stepper motor driver, HC-05/HC-06 bluetooth module. Here i have used HC-05 bluetooth module.
Connect CNC shield with arduino, connect motor driver with cnc shield and also connect HC-05 bluetooth module with cnc shield as below picture.
Connect motor with cnc shield
Also connect power supply to cnc shield between 12V to 36V dc range. Also give power supply to Arduino board of 5V dc using USB cable.