CC GG AA G (Twinkle twinkle little star) FF EE DD C (how I wonder what you are) GG FF EE D (Up above the world so high) GG FF EE D (like a diamond in the sky) CC GG AA G (Twinkle twinkle little star) FF EE DD C (how I wonder what you are.)
These types of songs are called "remixes". You will have to recreate the song, but you can search up the melodies/harmonies/etc. of the song to copy them to your song.
Note where middle C is on both clefs (for viola it's the center of the staff, piano treble clef it's the first ledger line below the bottom of the staff....
