how to "forget" an added keyboard?

I recently bought a separate keyboard for my MacBook Air. It's by Mofii on Amazon, is completely wireless and connects through USB. When I connected it, my Mac said some of the keys were unrecognized, and asked me to specify what "type" of keyboard it was. It gave me three options, two of which I don't remember, but I chose Japanese manufactured because that's what I'd thought the brand was.

But it seems I might've chose wrong, because some of the keys don't work at all now, and some are completely out of place (example: if I click the ":" it instead types a "/").

I need to know if there's any way I could access it on my Mac to "forget" the keyboard, or to change the option that I had picked?