From your photo, it seems you have some malocclusion of your teeth. The top front teeth usually sit slightly in front of the lower front teeth. In your case your lower teeth are in front of your top teeth.
The cause of this malocclusion can either be related to your upper jaw, your lower jaw or both. It's best if you seek an in person assessment so the correct advice about your suitable treatments can be discussed with you.
If you do indeed have a malocclusion, treatment would involve orthodontic treatment as well as orthognathic surgery. Hope this helps.
