Go ahead. Plug it in... unless your keyboard is not USB. In that case, you may have a problem.
I feel your pain. My dissatisfaction with the keyboard on my Microsoft Surface prevents me from using it more. It’s not a bad keyboard. I’m sure that it works well for most people. It’s just not particularly suited for my large hands and fat fingers.
The short answer to your question is yes. If you have a USB-plug keyboard, plug it in. It should start working in a few seconds. I do it all the time.
In fact, I have a friend who’s borrowing a laptop of mine that has a bad key on it. Rather than swapping out the laptop based on its usage, it’s more effective to just give her use a USB keyboard to use with it.
The only time that this may not work is if you’re dealing with an older keyboard – one with the round plugs at the end of its cable: the PS2 port, the PS2 connector, or the DIN connector. While there may be some USB adapters available for those, they may not work in a situation like this.
But if your keyboard is USB, plug it in! You can even plug in more than one keyboard. It will work.