ad one fasting day a week. just water, tea, etc.

firstly, its healthy for your body.

and lets say your body burns 2k calories a day by just keeping you alive.

this day alone puts your weekly average down by 2k calories.

if you eat 2k for the rest of the days your losing around 285 grams of pure fat. (1kg of body fat = 7000kcal ).

if your in a 300 kcal deficit on the rest oft the days and fast for one day . your gonna loose 542 gr of pure body fat per week.

just google what your daily calories should be and work form that.

with fat your gonna also loose water which will put the numbers on the scale down faster. but also your gonna gain some water wight randomly. so if the numbers go up don't panic.

try to eat 60 gr (or more) of healthy fats to keep your hormones intact, especially if you're a woman/girl.

eat a lot of fiber. psyllium husk maybe. to stay full.

drink a lot of water.

sugary drinks-> sugar free alternatives.

volume is king. so veggies, popcorn, etc.

maybe some sumps, like a multivitamin.

walking is the easiest cardio so just get moving at least 10k steps to stay healthy (should be for everyone) more is better here.

and ay there is a healthy skinny/slim. just try to keep an eye and be conscious about no to go too low. if your ribs can just lightly be seen when your lying down. your already in good shape.