That depends on:
How tall your parents are. If your parents are tall, you are likely to be taller than if your parents are short. But growth hormone treatment will not cause you to become a giant. Even with treatment, you cannot grow beyond the limit set by your genes – that is based on the heights of your parents.
How regularly you have injections. Having the injections regularly will help you grow to your full potential.
How old you are when you start treatment. The younger you start, the taller you are likely to be. But even older children can reach their potential height with growth hormone treatment.