and the point is the groove. Yeah, you can learn the notes and play them, but, if you don't have the feel, the swing, and the tone, it will never sound right. I play a Lot of New Orleans music (rock & roll started in New Orleans at Cosimo's studio - get the CD collection "The Cosimo Matassa Story" a 4 disk set - now

) , and, when I have occasion to teach the style to neophytes, the first thing I tell them is to LAY BACK!
Josephine is a perfect example- it rolls, all of Fat's stuff does. Fats was a blues player before he picked up on Professor Longhair's style and made it into his own thing. And, like a lot of New Orleans music, it swings.
You should begin by playing a simple shuffle with a metronome, until you can land on the beat all the time, then work on playing behind beat four. The next thing is the One to Five- a D to an A, bounced in a dum, - ta-dum way, still laid back. These two patterns are the basic of early rock. There are others, like A / C# / E / F#, but these are the ones you have to have down to play it with the right feel.
But get that collection and learn it. You'll be pleasantly surprised at what you hear and read from the notes. Do that, and you'll have a solid foundation for playing rock, from where it came from in the way it was played.