I have an older laptop that I am cleaning up for my son (HP Pavilion g6 - AMD A8-4500 with Raedon HD Graphics). It was Windows 8 but I recently did the free upgrade to Windows 10.
Ever since the upgrade, the Ctrl keys do not work. The onscreen keyboard control keys work fine. I went into ease of access and turned on the "beep" and sticky keys and there is no beep when press ctrl but fine with alt/fn etc.
I have googled and tried a few suggestions with no success so far. Unfortunately I do not have an external keyboard handy. I feel it is a software issue as it was working fine under the old OS
System Configuration: Windows / Chrome 85.0.4183.83