The piano is a member of the percussion family and is very easy to make a sound out of.  Most instruments you have to blow into the horn like brass and woodwind.  However, in the percussion family you hit or strike the instrument.  In this case you push down the keys.  The notes of the piano go like this:
 
 

                                        C        D        E        F        G           A        B        C        etc.
 
 
 
 

             Once you get good at the piano, like every other instrument you can play in concerts and other things like that.