I hate my body

I’m a 17 year old girl. About 5’3 and last time I weighed myself which was bout over 6 months ago I was 116lbs (53kg). I look really thin, I hate it! I wouldn’t say I eat too much or too little....Just normal and round my period I eat a lot. But I never gain weight, & even when I do, it’s just a little bit. How can I gain weight? Without exercising like gym type? I don’t like my body at all, I’m skinny and look like a little boy. No thick thighs, bum or curves😩😩HELP!!