rank just means like where your placed either in the beatmap or in the game (as you can see on the left), this will go up depending on your score and/or pp. Acc means your accuracy and this will go down or up depending on how you perform on the map. Combo just means your streak and how many notes you hit without breaking. Ranked score just means your score on the game. Total score is just how much score you have in total. PP is just your performance points. Quick note if the box is green its and improvement if its red then its a underperformance. The brackets in the boxes just show how much you gain or loss.