Make and model of PC. Laptop or desktop? Type of mouse and keyboard, USB, PS2, etc.? Did these items work before? Or are they brand new? Windows 10 automatically updates certain drivers, ( unless you disable such driver updates) and rolling back the driver updates in Device Manager might help..
If you're using a USB style mouse and keyboard, and please recognize I'm just checking here.... Have you changed the batteries lately? If not, please do. Made sure both mouse and keyboard are turned ON? If you start the computer in Safe Mode, do the devices work now?
Sometimes the BIOS needs to have "Legacy" USB options enabled for mouse and keyboard to function. I'll recommend testing everything with a PS2 style mouse and keyboard to verify everything and do make sure that drivers are correctly installed in Device Manager.
Hope this helps and let us know more.
Grif
I've got a problem when start up my PC then I try to put in the password it won't work my mouse or keyboard won't let me put anything in so I tried a different one and it still didn't let me. I cant do anything with the pc

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