Learn to play the melody of this song with your right hand alone.
Use correct fingering (the numbers between the treble and bass staves) and you will have a smooth melody.
Add automatic chords by reading the chord letters above the treble staff
The rhythm you add will be something suitable for 4/4 time such as 8 beat, pop, or swing. Begin ver-r-ry slowly with a metronome speed of 60.
When you can play it well at that speed, then try it faster.
Listen to the song