Prediction models and correlation in R

Forgive if I am not a seasoned statistician, I am starting out since some months. It's very difficult to starting out, I think you know it.
I don't know many terms, and what it's super-difficult is also to learn R language and tools in R, how do they work.
I am mining data on tennis. I have a lot of data about a tennis player.
I want to find some correlations.
I target tennis players. I want to know if there is a correlation between a tennis player's victory and the number of ACEs made during his last 30 matches. Can you help me write this in R?
What distribution should I choose? Poison? What to put on the axis of the abscissa and what to put on the axis of the ordinates? What are the variables in this case? How to write this in statistical terms? what distribution to use?
ALSO: How to have a model that predicts what would happen if the number of aces were below a certain threshold? Thank you so much if you could answer to me
Thank you