(Raspberry Pi 4 and Python) Raspberry Camera mode raise picamera.exc.PiCameraMMALError and picamera.exc.PiCameraError

Question

System: Raspberry Pi 4 model B, use external USB Logitech camera

I'm follow the youtube tutorial but get picamera.exc.PiCameraMMALError andpicamera.exc.PiCameraError

Relate discussion on other site 2021 (I didn't get their solution): "Camera issue, no idea what the problem is"
https://forums.raspberrypi.com/viewtopic.php?t=324702

- The python code:

from picamera import PiCamera
import time


print("= = = = = == = = = ")
camera = PiCamera()

camera.start_preview()
time.sleep(2)

camera.capture("test.jpg")

- The whole output:

mmal: mmal_vc_component_create: failed to create component 'vc.ril.camera' (1:ENOMEM)
mmal: mmal_component_create_core: could not create component 'vc.ril.camera' (1)
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/picamera/camera.py", line 456, in _init_camera
    self._camera = mo.MMALCamera()
  File "/usr/lib/python3/dist-packages/picamera/mmalobj.py", line 2279, in __init__
    super(MMALCamera, self).__init__()
  File "/usr/lib/python3/dist-packages/picamera/mmalobj.py", line 631, in __init__
    mmal_check(
  File "/usr/lib/python3/dist-packages/picamera/exc.py", line 184, in mmal_check
    raise PiCameraMMALError(status, prefix)
picamera.exc.PiCameraMMALError: Failed to create MMAL component b'vc.ril.camera': Out of memory

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/joy/Desktop/camera.py", line 6, in <module>
    camera = PiCamera()
  File "/usr/lib/python3/dist-packages/picamera/camera.py", line 431, in __init__
    self._init_camera(camera_num, stereo_mode, stereo_decimate)
  File "/usr/lib/python3/dist-packages/picamera/camera.py", line 459, in _init_camera
    raise PiCameraError(
picamera.exc.PiCameraError: Camera is not enabled. Try running 'sudo raspi-config' and ensure that the camera has been enabled.

---

• The youtube tutorial I follow:

How to Take Photos and Videos with Raspberry Pi Camera Module
https://www.youtube.com/watch?v=nx8gDSS1vO4&list=PLnjnmu-sbNYMvMiXd-y5t7fYts1N0hmuI&index=3&t=331s&ab_channel=TechWithTim

• Troubleshooting:
  (Camera is not enabled. Try running 'sudo raspi-config' and ensure that the camera has been enabled.
  --> The follow picture I just make sure the camera is enable, maybe because I used external usb logitech camera )

https://ibb.co/Jyxtbfv
https://ibb.co/CHrWRH1

I'm the python beginner, and first day have Raspberry Pi, stocking on camera setup, how can I fix this?