Can someone please give me some information/articles/studies on low fat diets vs high fat? im so confused!?

i have read higher fat can actually be better for you, but you always hear the emphasis on the low fat. does anyone really no which is better (healthier). right now i have low energy and i feel kinda week and i wanna know which nutrition will help me feel better, look better, and improve my mood. ( btw im not overweight).