Try running Windows in Safe Mode to see if the problem persists:
https://www.dell.com/support/kbdoc/en-uk/000124344/how-to-boot-to-safe-mode-in-windows-10
If it disappears in Safe Mode, then it's clearly a software problem. If so, when running Windows normally again, enter Task Manager (via right-clicking on a blank space on the taskbar at the foot of your screen) and look for anything that possibly shouldn't be running and try closing it. Also run a full scan with your anti-virus software AND run a malware scan with AdwCleaner:
https://www.malwarebytes.com/adwcleaner
Still assuming that it's a software problem (which disappears in Safe Mode), if all else fails consider resetting your PC. (As long as you choose the correct option, all of your files - such as documents, videos and pictures - will be retained but you'll need to reinstall any software that wasn't pre-loaded on your laptop):
Start > Settings > Update & Security > Recovery > Open Recovery Settings > Reset this PC > Get Started.
If the problem doesn't disappear in Safe Mode, then it's either a problem with the keyboard itself or its driver. Try updating or reinstalling the driver:
https://support.microsoft.com/en-us/windows/update-drivers-in-windows-ec62f46c-ff14-c91d-eead-d7126dc1f7b6