As I develop I realize that my body stays the same way, I mean I don't look like my age.I don't even grow beards or hair in my chin. I was wondering if anybody has any idea as what my be the cause and how to resolve.

If you look younger than you really are, you may eventually think that it is a blessing!

Not to lessen the problem posed in you question, though.

It would help in answering your question better if you would state how old you are and of what nationality/race you belong to.

The cause could be hormonal Hypopituitarism - My Child Has - Children's Hospital Boston (http://www.childrenshospital.org/az/Site1133/mainpageS1133P0.html)
Or hereditary. It might also be merely temporary.
Some people take longer to develop than others. Barring the above, the condition might be due to malnutrition. In that case improvement in diet and taking a multivitamin supplement might help. Or the whole thing could be within the normal range. As the poster above suggests, providing your age and race would be helpful.