Try connecting a USB external keyboard and if it works properly then you will probably have to replace the laptop keyboard. If the system is under warranty still then call Dell tech support. I have no idea if you purchased an extended warranty. I also cannot point you toward a source for the keyboard as you did not post the laptop exact model number.

Most of the time, these are software issues caused by drivers or updates or changes to your computer that you can often address through another update or a settings change

The laptop keyboard can be replaced. It's not difficult, and there are no long-term consequences. It will work, but if you don't push down forcefully, it's pretty easy to become caught at the "bottom" of the keyboard. This signifies that the keyboard is no longer functional. Replacing a laptop keyboard is not as difficult as it seems. The most crucial thing to accomplish before you begin is to choose which keyboard you need.