i'm just bangin' on my ol' piano...gettin' in tune with the straight and narrow  

Funny how things can come about.
Just out of thin air.
Now I am am no maestro by any measure but I do know this, I lie to toy around on my gf's keyboard.
I can not read a single note.
But I know songs from what I remember.
I can hear a song and 'go with it'.I am not really able to play with 2 hands which would give it a fuller sound.
I am going to start studying notes.
What are some simple songs that use 'basic notes'?
Like, for example, could I possibly play a song using the A,C,E notes.
I know that sometimes toying with a guitar, again not knowing any notes, but just messing around...wow!
I have to hand it to anyone who can read and make sense of what they are doing.
Hehehe.
That is quite the task:)