How do I make a damage script related to dbz?

Hey! I'm currently on a project of making a dbz game, but right now the entire groundwork is currently work in progress, I'm a starter in scripting and I have no clue what to do in what ifs to make a formula,

I need to create a formula such that if a power level of a person is 100

Every attack damage is + and Def increases Like a hit does 2 damage in general, i want to add 1 more to it, If a beam does 5 damage, i want to add 2 more to it, basically a % to a stronger attack and damage reduction, but I not only just want every 100 power level to add stats, like if u have power level of 10,000. U won't require just 100 each but like 1-3k or like a % of powerlevel based on unit, and I also want it so that every entity , enemy or player has a powerlevel, and also I could customise it, so I would scale how much I want power level of this NPC and how much player powerlevel is required so I would scale and balance the game out, I also want that if u kill a certain enemy, like boss u get more power level, and every attack u spam gives u a certain power level, there are some cool dbz games in roblox and I can't figure their formula, so I just need how to, if u can't do it but it's possible I just need a good explanation and examples of when to type this and why. So I could just get started because it's way too complicated!

I have no idea or clue how to put my imagination in scripting since I don't know possible algorithms and combinations, i want somebody to explain and give a example. The script and concept should be pretty much self explanatory so I could tweak it and scale the game

Thanks! I will give a Big shout out on my server and premium stats ! (If u decide to join if the game is popular somehow)