my pc turn on, monitor works, but working mouse and keyboard will not work. What do I do?

[Yannnx]

My keyboard was working but then I watched a video on YouTube and I uninstall USB ports, said they will install again when I restart my PC. I did that and now nothing is working, except monitor. I can not go to the settings cause I have to enter the password for PC, but I can not.

 

[CountMike]

Which kind of computer and which OS ? There are thousands of combinations so how could anybody guess what you have ?
If it's a desktop computer and has PS/2 connector you can try with a PS/2 KB and/or mouse.