I am 18y old and 5.7 right now..how to increase my height ? my parents height 5.9 and 5.0

Unlikely to happen: Good basic nutrition, rest & exercise help a person maximize their growth. Their are no special diets or workouts. At 5'7" you have reached the height expected as estimated from parental height. (ave + 2.5 in for a male) at 18 your growth centers have likely closed & no more linear growth is expected.An x-ray of your hand & wrist could verify your bone maturity & see if any more growth is possible.