Ctrl/Alt Stuck, can't log in to windows!

This has really ruined my day!

This morning, after a Windows 10 update on my pc I started having issues with the keyboard switching to the Alt Gr mode on its own. It would switch on and off seemingly at random, before finally sticking permanently. To be specific, when the on screen keyboard was displayed, both ctrl keys and alt were constantly pressed.
I tried various solutions, including a different keyboard, to no avail. I thought it might be a problem with the settings, but rebooting turned out to be a really bad idea because now I cannot log in. The mouse is not properly usable either. Tried going into safe mode but it wants keyboard input to select that option.

Is there anything else I can do at this point? I'm totally stuck. Please help me if you can!

Hopefully, you have a Macrium Reflect Disk/SSD image you can restore if not it sounds like your going to have to try to save your data from that drive on another computer and clean Install!!

It's apparently too late now but notebooks have proprietary drivers for Keyboard touchpads etc. and WU has a tendency to install native windows drivers which can cause the issues your experiencing.
I would go to the manufacturer support website and download the latest Windows 10 driver for your notebook have them ready to install right after a WU. I would also block driver updates once you get up and going again Enable or Disable Driver Updates in Windows Update in Windows 10 | Windows 10 Tutorials

I just assumed you have a notebook since you haven't fill in your computer specs its hard to help you if we don't know what your working with System Specs - Fill in at Ten Forums | Windows 10 Tutorials

Thanks for responding!
My OS is on an ssd, and most of my data is on a separate internal d drive. Would the clean install leave the d drive untouched? My documents, downloads, etc. Folders are located there. Everything super important is on a NAS.
I can't access system information right now, but the computer in question is a desktop pc running 64 bit Windows 10.

Update; I managed to get into windows by booting up with no keyboard attached and using the onscreen keyboard. I'm wary about putting the keyboard back, going to try what you suggested before if I can figure it out! Thanks!

Yes, I would disconnect any other physical drives to protect them. If desktop just pulls the power plug on each of them until you get this fixed.

If All in one or notebook open the back and remove any 2nd physical disk/SSD

That SSD wouldn't happen to be an Intel SSD !!!! there are warning about 1803 and Intel SSD's the update had been pulled from WU for Intel SSD Users??? MS and Intel are working on the issue,

Yes if you're windows you should be able to roll back to 1709 where you had no issue and reconnecting your keyboard should not be an issue and you shouldn't lose anything

If the keyboard is Bluetooth for sure update the Bluetooth driver to the latest Windows 10 from your manufactures support website or if addon, get the latest Windows 10 driver from the manufactures website.

I have to say I'm using Logitec mouse and keyboard and have no issues with 1803 but I don't think they are Bluetooth but some other wireless technology

Rollback didn't seem to help so I let it update again. I wish I could uninstall the keyboard drivers without the keyboard being present

'Keyboards' does not appear in the device manager while there isn't one plugged in. Plugging it in made 4 devices appear under the heading. I uninstalled all of them, then unplugged the keyboard briefly. Then I clicked scan for hardware changes and the keyboard reappeared. For about ten minutes the keyboard was completely back to normal, but then it suddenly stopped working again, same issues as before.