I am using a Dell laptop, and the USB connection ports does not work

When you connect an USB device to your computer you get a sound indication that power is being supplied to the device and it is connected.
If you don’t, then check in Device Manager that the option for the computer to control power to the USB Root Hub device is disabled. Double click on Universal Serial Bus Controller for a drop down list. Check all USB Root Hubs, right click on USB Root Hub and select uninstall (Perform the same step for USB Root Hub only). Restart your computer after doing this for it to come into effect.