2 Thread running, if thread 1 change a value thread 2 will be affected

I have 2 Function the 1st one is atomization using Pywinauto and the second function is screenshot recording using opencv

this is my code on my second function

def record():
    # display screen resolution, get it from your OS settings
    SCREEN_SIZE = pyautogui.size()
    isRecording = True
    # define the codec
    fourcc = cv2.VideoWriter_fourcc(*"mp4v")
    # create the video write object
    file_name = asksaveasfilename(confirmoverwrite=True,defaultextension='.mp4')
    out = cv2.VideoWriter(file_name, fourcc, 20.0, SCREEN_SIZE)
    print("Recording Started...\n")


    while isRecording == True:

        # make a screenshot
        img = pyautogui.screenshot()
        # convert these pixels to a proper numpy array to work with OpenCV
        frame = np.array(img)
        # convert colors from BGR to RGB
        frame = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)
     
        cv2.imshow("Recording...", frame)

        if isRecording == True:
            out.write(frame)

        
        if cv2.waitKey(1) == ord("q"):
            cv2.destroyAllWindows()
            out.release()
            break

so While isRecording is True it will continue to write.

On my Main Function or the first Function

def installer():
       installer.child_window(auto_id='deviceSelectionNextButton').invoke()
       progress = app.Dialog.ProgressBar
       status = progress.exists() 
                
       while status == True:
               isRecording = False
               if progress.exists() == False:
                  isRecording = True

this is waiting for the progress bar to finish or disappear.

What I am trying to get here is when its Loading it will turn isRecording to False which will making the function recording stop write and when its done loading it will turn isRecording to True and continue write.

Recording is running at the same time as Installer. Since Recording constantly screenshot and installer is an atomization of an application, the Installer function runs the Atomization and the Record Function records the Atomization