Hi... I'm 5.5ft high . My father is also shorter than me . I'm 18 years old . Suggest me some tips or exercise to grow taller...

You will grow as tall as your genetics allow.
There isn't anything you can do about that.

If you are already taller that your parents, then that's most likely as tall as you will become.

While you can't actually grow any taller than your genetics have decided you will be, you CAN make the most of your height.

Improve your posture. Slouching can take several inches off your height. Just learning how to sit and stand properly can make you look taller than you are.

Wear clothes the elongate. Fitted shirts and pants make you look taller than baggy clothes. Thin, vertical stripes (like pinstripes) can also make you appear taller. Avoid ill-fitting clothes and horizontal stripes and patterns.