Creating mobile game

Question

If I were creating a game with a leveling up would system would I make a class such as Class increaseATK
Class increase DEF
And make them private
Would not work in theory to make them only accessible by the the character or player to only increase ATK by giving certain object (weapon) a value and adding that value to said class and using a simple addition function to add on to the already atk power. I haven’t fully grasped the idea yet but I believe it’s something like this. Anyone know how to do this. And are open world rpgs hard to make. I

Answer 1

maybe but i dont care how hard it is. not gonna stop till i reach the end goal. i just wanted some insight thats all