How to break a loop in this case?

[DeaD_EyE]

I changed your code a bit.
Does marketloop require access to key events?
If it's the case, code needs to be changed. Again.

import pyautogui as pg
import time
import keyboard
import random
import win32api, win32con
import threading
from pynput.mouse import Button, Controller
from pynput.keyboard import Listener, KeyCode


class BuffItems(threading.Thread):
    def __init__(self):
        super().__init__()
        self.running = False
        self.pause = False
 
    def start(self):
        """
        Duplicates the start method of threading.Thread
        """
        if not self.running:
            self.running = True
            super().start()

    def stop(self):
        self.running = False

    def pause_toggle(self):
        self.pause = not self.pause
 
    def run(self):
        while self.running:
            time.sleep(0.5) # to reduce speed
            if not self.pause:
                marketloop()


class KeyboardControl:
    start_stop_key = KeyCode(char='s')
    exit_key = KeyCode(char='q')

    def __init__(self):
        self.listener = Listener(on_press=self.on_press)
        self.listener.start()
        self.buff_thread = BuffItems()
        self.buff_thread.start()

    def __enter__(self):
        return self

    def __exit__(self, *args):
        self.buff_thread.stop()
        self.listener.stop()
        
    def on_press(self, key):
        if key == self.start_stop_key and self.buff_thread.running:
            self.buff_thread.pause_toggle()
        elif key == self.exit_key and self.buff_thread.running:
            self.buff_thread.stop()
            self.listener.stop()

    def join(self):
        while self.buff_thread.running:
            time.sleep(0.1)


def marketloop():
    print(time.time())


def main():
    try:
        with KeyboardControl() as control:
            control.join()
    except KeyboardInterrupt:
        print("\nReceived SIGINT. Exitting programm.")


if __name__ == "__main__":
    main()