Game scoring

Hey guys, this is my first post!

I’m creating a simple game where as you go along you earn and lose points based on the decisions you make (similar to the classic choose your own adventure books/apps) the final outcome will be based on the amount of points you have accumulated, and it will work on a if/else basis where you will be redirected to a different scene depending on your points score. I’m not sure how to create the points system, could anyone give me any tips or point me in the direction of a suitable tutorial?

many thanks for your help,
billy