I m so weak tell what should i do i want to be healthy person but i m so weak and skinny u cant imagine?

i m 24 live in karachi pakistan i masturbate daily i m so weak my arm like 10 years old boy my bones so skinny i feel embarr when i fold my sleeves and my whole body shake all time and if i do exercise like push ups then my muscles shaking a lot please help me i will be very thank full to you people thanks in advance