Hello,
Welcome to the Microsoft Windows Community.
Good afternoon, @Katherine Bresnahan . To provide more accurate assistance, please let us know the make and model of your computer and follow the steps below to run some tests:
1. First, check if there is a keyboard lock key combination; usually, this involves pressing the Fn key plus a function key (look for a key with a keyboard icon).
2. If that doesn't work, open the On-Screen Keyboard and try typing. If it works properly, the issue might be a hardware defect in the physical keyboard; in that case, you will need to take the computer to a service center for an in-person inspection.