Well I Will suggest you to updated your webcam driver and also your audio driver for mic issue because some time an outdated driver can also create these kind of issue in your system.

Make sure the camera is enabled in the BIOS of your Dell laptop. Restart or power on the computer. When you see the Dell logo during POST, press the F2 key once a second to enter the System Setup. NOTE: When the computer boots into Windows, restart the computer and try again.

i can't see camera  enable or disable option on system setup

no camera drivers in device manager 

1. Tell us your laptop model and what OS you're using.
2. Make sure you installed any required chipset drivers from Dell support site.
3. In Device Manager, look under Imaging devices.
4. In Device Manager, uninstall camera drivers. Then reboot and Windows may install the required driver.
5. Check if your webcam has a manual shutter that you must slide to one side to uncover the camera lens (I don't know if your laptop has one, because you didn't tell us your laptop model).
6. When did the camera stop working? Was it after you performed a clean install of Windows or upgraded to a newer Windows OS?

inspiron 3593 windows 10

no camera drivers in device managers 

i updated to wndows 11 but no

after i dwngraded to windws 10 after 1 year 

When I suggest a task, you need to tell me if you did it and, if you did, what result or behaviour you saw.

• Did you install the chipset drivers?
• Did you look in Device Manager, under Imaging devices and under Cameras?
• Did you check for a physical shutter?
• Has the camera ever worked?

In Device Manager, View | Show hidden devices. If your camera appears under Imaging devices or Cameras, uninstall it. Then reboot and Windows may install the required driver.

If the driver does not get installed or camera still won't work, look in in Device Manager under Imaging devices or Cameras to see if a device is listed there, showing hidden devices if necessary.. You can right-click the device and under the Details tab you can find Hardware IDs that you can search for to help to identify the device.

Try the steps in this Microsoft troubleshooting document for camera issues in Windows.

Also try Testing, Troubleshooting and Resolving Driver Issues on your Dell Webcam.

not in imagine device