How do I get 4 Videos in one frame using OpenCV. I know this has been asked before, but I have yet to find code that works

Question

I am new to Python, and I am learning the hard way. I'm using OpenCV to do this on a raspberry Pi 4 with 4 USB webcams for now. I am getting video, but I am unable to get 4 videos in one frame. Most of the code that I have found does not work. I am using Visual Studio to do this. This is one example that I am using.

import cv2.
import NumPy as np.

# initializer
cam0 = cv2.VideoCapture(0)
cam2 = cv2.VideoCapture(1)
cam3 = cv2.VideoCapture(3)
cam4 = cv2.VideoCapture(5)

while True:
   ret1, frame1 = cam0.read()
   ret2, frame2 = cam2.read()
   ret3, frame3 = cam3.read()
   ret4, frame4 = cam4.read()

   if ret1:
     cv2.imshow("cam0", frame1)

   if ret2:
     cv2.imshow("cam2", frame2)

   if ret3:
     cv2.imshow("cam3", frame3)

   if ret4:
     cv2.imshow("cam4", frame4)

   if cv2.waitKey(1) == Ord('q'): 
      break

  cam0.release()
  cam2.release()
  cam3.release()
  cam4.release()
  cv2.destroyAllWindows()