Connect Keyboard to Ci1 ??

Hello, I bought a Ci1 to connect to a laptop for a 15 year old to record her voice and keyboard and now suspect I bought the wrong thing! It’s fine for the microphones, but don’t know about the keyboard.

My question is this, is there anyway of directly connecting a keyboard through the Ci1 to enable recording on a laptop…

If not, could I connect the keyboard through a mixer and then through the Ci1 to the laptop (I don’t have a mixer yet, but will get one).

And if the answer to both of those questions are “no”, then what is my least expensive way to get the keboard into the laptop to utlize with the recording software?

Thanks for any help.