If you opened . json file, you can just change numbers next to the thing you need to make higher. Find with Search option words like Food, base and others. When you change things you need, you can return to game, tap Load and tap arrow down on any empty save tile. Then choose the file you made.

I don't like doing it because it goes against the creator's intentions and I really do love the game. The way you do it(if on windows) is by going to the folder with your save in it. It is easiest to access it in game. You go to either your game profile, or the game save. In your case you want to go to your save. If you notice, your save numbers dont exactly match up with the numbers you see for each save in the save menu from the game. Save1 in the folder is Save2 in the game menu, so be careful. You go to the stat that you want to change, which will be the top set of stats(since there is like a set of 2 stats, the beginning and your current). You want to go to these first stats, and simply change the value you have.

I personally dislike this because the grinding is the fun part. I got myself all the way to level 111 so that i could have everything maxed and it was worth it for me. I got all of the scenes by discovering them myself. I got as close as possible to getting full game completion % by myself. It makes the game itself that much more enjoyable. The moment you start changing saves is when the game feels pointless because you yourself took the point out of the game. It made it fun. If you need gold or food, just kill the demon king. It is a repeatable fight.