Hi! With regard to the Jeff Porcaro drum part for Rosanna, the foundation for the beat is the Bo Diddly rhythm, but played between the bass drum & snare instead of on the toms. Jeff masterfully includes very tasty
ghost notes (notes that are very subtle and soft) on the snare in between the main beat, which results in the amazing drum part we all know and love. Keep practicing! It's not the easiest beat to master, but it can be done! I love playing it, everyone recognizes it instantly! He goes into specifics that are very helpful in his teaching video. Unfortunately, the title for it escapes me. You might be able to access it through the internet, since there's so much info available now! But, if you start with the basic "Bo Diddly" beat and expand on that, as you get more comfortable with it, you should ultimately be able to play it after a while of practicing. I suggest practicing along with the song but, start simple with just the basic beat (a doted 16th note) shuffle between the bass drum, snare & hi hat. I suggest learning the beat without trying the ghost notes first. You can get more technical after you become familiar with the foundation of the beat. Hang in there! It can be done!

*And it's really fun, too! Sincerely, JP Lindsay