DataStore2 Increasing a value if its less than or equal to the backpack amount?

So I'm trying to make a simulator and increase the value of Bones (Which is randomly chosen) the player gets when they kill an NPC but I want to make sure it doesn't go over the backpack amount.

I don't have a script unfortunately cause I'm unsure on how to do it. If you could help please make an answer to the question or just DM me on discord 0Vyp#9314