Iam new in swift and i need some help

Question

Hi developers
Really happy to join ur community
Iam new in programming
And i have finished my online course with some exceptions
Question: i want to develop an app to calculate scores for cards game that i always play with my friends
Hint: some cards adds points and some minus points and after all rounds finish it shows scores and winner
I know rules of game that i want
I have finished design of app
But i can’t start coding because i don’t know from where i should start ( put game rules in class ? ) or code by code
And i have a missunderstand in all courses and videos i have took
It’s about connections and segue between controllers

Conclusion : let me know from where i can start
Or let me know if there is interactive online course because i have alot of questions