Is it healthy to eat the fish, chicken and pork fats and skin? Attempting LCHF to restore period after anorexia now... (bmi 18.5)

Not LCHF. Trusted experts would advise against this diet and recommend frequent (5-6) meals daily, nutrient rich foods: whole grains bread/cereal/pasta; dairy; lean protein; nuts, healthy smoothies/shakes; snacking on nuts, cheese, peanut butter; adding cheese or milk to soups/stews; occasional pie with ice cream!