Girls, can you tell me if it's possible to increase milk fat with food…

Girls, can you tell me if it's possible to increase milk fat with food? My child hasn't been eating much, started giving him formula 30 ml, he doesn't want to eat the mixture at all, he only needs breast milk, I attach him to my breasts often, they told me that I need to drink fatty broth, buns with oil, tea with milk, I already feel sick from these buns and broth, what else can I eat? It's my first baby, I was born on IV therapy, so I haven't encountered such a problem.