How would I go about making step-by-step fighting system?

Hello! So I want make some unique combat system which is step-by-step. If you are wondering what I mean then I will take in example a pokemon games and Adventure Story. The thing is that I don’t know how would I make it. From what should I start and etc? Can you please help me.

If you don’t know how to script you might as well just youtube a free combat system because im pretty sure nobody is gonna sit here and write you a whole combat system for free.

No, I know how to script. Im just asking from what should I start. Something like that. I just can’t imagine how would this work in my brain.