Try the onscreen keyboard, included by Microsoft, and demonstrated here. Does that work? If not, you have a software problem with Windows or an app interfering with Windows.
If the onsscreen keyboard and do work, do a Shutdown of your PC, unplug the keyboard and then plug it back in, and retry it. Should your keyboard still be recalcitrant, then replace it.
.
And, when you find an answer, click on the checkmark at the left, to show others it worked. That also boosts the cred of the person who provided you an answer, which helps them.