were does one go to find a tutorial on this subject?
There isn't one AFAIK
You need to be more specific, since I don't even understand what you are looking for. Random and story battles are two very different things, however at this point Idk if you are asking about event editing, script changing, battle stats, or yelling at the screen until it does things. These are all different. Please be more specific in the future
Changing battle formations for example. The opening fight at oreborne monestary were you have Aigris, Gafgarion, Ramza, Aigrias' 2 knights and Lad the squire. Chaning it from that formation to just Gafgarion Aigrias and Ramza.
Or chaning fixed loadouts for example starter weapons changing a chemist dagger to the platinum dagger.
and other things like that
Have you ever looked at the tabs? This shouldn't exactly be hard to figure out on your own...
There's no tutorial on this, because it's incredibly obvious in the Patcher. Go to the ENTD tab and have a look. Everything you mentioned here can be changed in seconds.