It's a bit of trial and error, you can use save editor or any other site that supports the type of rpgm files. There are 2 main things to edit:
1. characters/recruits: you will see the name along the stats of every npc available in the game and in your party, just scroll until you see what are you currently running and edit the values, just be careful as how shitty Orachi put his "anti cheat saving system" in some cases if you put lets say a value like 900 or 15000, your save will just load up and instantly close becoming unusable (so making a backup is always recommended) some characters and items allow bigger or smaller values so fyi.
2. items: this is easier as you just have to remember how much you had of each (potions, the stupid save camp tent, etc) and you can pretty much know what are you editing.
(Bear in mind that I haven't played the last version posted here, so idk if he patched it or not)