What is the best food for 10+ cats?

So the hag is soon to be 10 , I recently took her to the vet bc she had diarrhea with blood (she had blood on her stool before , I usually just adjusted her diet to soft food and fed her pumpkin and she got better , so I thought it was normal especially when I googled it) I immediately took her and turned out her intestine were very inflamed (but her blood test came out great and she had no kidney problems , the vet even complimented my care and supplement because I showed her of course 😂 sorry I’m bragging. I’m very proud.)

Anyways, that vet told me that her food wasn’t very good for her it’s not suited for her age .