Mouse not found error

Projects General Guidance
1

I am trying to do two different set-ups. I tried both of these projects.

First I tried https://www.arduino.cc/en/Tutorial/KeyboardAndMouseControl

And I keep getting an error 'Mouse' not found. Does your sketch include the line '#include <Mouse.h>'?

Next I tried this

And again I get the same error.

I am assuming it is something obvious, but I am a newbie.

3

Sorry about that.

I am using a Leonardo board.