MacBook Keys not typing

computer frozen while browsing web, would not allow trackpad or cursor movement or hard restart.

allowed it to “sleep” and hours later the password page appeared. Spacebar triggers screen to come out of hibernation; trackpad works. Same happens when I plug in an external keyboard and Bluetooth mouse. No typing appears in the password area. So I’m unsure how to get access to the computer. Oddly, I tapped every key and it turned on a webpage audio link (in one of the 50 tabs open in a Chrome browser), but that page is not visible—only the computers secure login page.

computer is 5-7 years old, I think. Not sure which OS but have updated within the past year.

any suggestions?