Too much contradictory and faddish ideas out there about what is a healthy diet.
Even OP picture, at a glance appears fundamental, but are the areas supposed to represent relative volumes? Yes? Then exactly how the fuck is it healthy to consume a fuck load of plant oils (bottom right of pyramid )? That makes no sense at all.
General rule I stick with is half of your plate should be veggies, one quarter carbs, one quarter meat. Avoid white colored foods except fish. Avoid any condiments. Simple, visually easy to address. Learn to cook and you can make anything taste great without adding shitloads of salt, fat, oil or sugar.
But most importantly learn how to NOT be a prima donna. People who are fussy about food, wont eat certain types, wont eat anything unless its a fucking "taste sensation" ( exclamation mark, lol, smiley face), wont eat the same food twice in a row. Fuck, I would like to drag them out and stick them on a desert island with nothing to eat except some fish heads, raw cabbage, and rice for a few months.