I have a slight over bite and it is slightly visible on my chin/jaw. i am 21. could braces fix both of those problems? if yes in how much time

Probably: Probably. Depending on degree, oral & maxllofacial surgery/braces sometimes both required. Get opinion from orthodontist.

No, : If your overbite is slight, braces could probably fix it but braces will not change your chin jaw position.

Overbite/overjet: In an ideal bite there should be covering of the lower teeth by 1-2mm( overbite). There should be 1-2mm extension froward of the upper teeth in front of the lower teeth(overjet). Good orthodontic care deals with function(good bit).

Likely: hard to tell time without seeing your teeth. The national average for braces is 31 months but that said most of our cases are done in 18-24, so it can vary a lot by provider and case.

Usually Yes.: Depending on the severity of your issues, it can often be corrected in 9-24 months depending on the training of your orthodontist and the technology used. Orthodontics can absolutely change your chin position if done properly.

Absolutely: Type of treatment, appliances, need for extractions or jaw surgery, type of alliance, etc. is best determined after an initial examination (usually free) by a qualified Orthodontic Specialist. Average time in Rx approx 18-24 months. Beware the quickie/cosmetic only approach. See a Pro, she an Orthodontist.

See Orthodontist: Many orthodontists in USA offer an initial complimentary consultation. This allows you to find out what type of treatment for your individual situation is recommended and get all your questions (time, money, etc) answered. Best of luck!.

Overbite: Correction of overbites cannot be determined without proper records. It is also important to determine if the overbite is dental, skeletal, or a combination of both. That would determine what type of treatment will be able to address your "overbite" concerns.