Windows 10: Add your Microsoft account

I was entering my pin and logging into my PC as one does, and my keyboard worked fine. But then, a "Add your Microsoft account" screen popped up, and I thought that it was because the last time I logged in I scheduled an update for my PC I'm kind of behind on updates. So I assumed that this just came with the update and it was mandatory. So I tried entering my email, and it auto filled, but when I tried to enter my password, the keyboard wouldnt work, and like I said, it worked when i entered my pin..The only buttons on my keyboard that work on this screen are the power button and the enter button. I tried replacing my batteries it's a wireless keyboard and the chip is for the mouse and the keyboard, but the mouse worked fine I tried powering my PC off and restarting it, I tried using it on a different device, and it worked, i tried using the onscreen keyboard, and it wouldnt enter any letters or numbers into the text box, which I had clicked and still didnt work, etc..etc. I cant get it to type anything, And I cant exit this screen, My computer is getting kinda old and it's starting to work a lot less ex: chrome taking 28 minutes to open and it's about time to get a replacement, but I cant even get INTO the computer now, and I need to be able to use it. Its been like this for three days. Sorry if this was long, i just wanted to make sure i explained it properly


Help!

:)