It depends on the amount of malalignment you have in your teeth. Hence it can take anywhere between 6months upto 3 years. Your concerned orthodontist can answer this accurately.

I think your orthodontist would be in a better position to explain you about the duration , the duration is not fixed in case of braces , it can vary from patient to patient.. hope the question is answered

Fixed orthodontic treatment can take anywhere from 6 months to 2 yrs. It depends on many factors like age, growth rate, severity of the problem, bone density, etc. So no one can say accurately how much time it will take in your case. But since you are not in a growing phase anymore, it will probably take longer than 6 months (maybe an year). Also, you did not provide any pic to show what condition it is in right now. So without that no one can give an accurate timeline for the treatment. The only thing I can say for sure is that after the treatment is completed, you have to wear a retainer for at least 6 months. 

Depends on condition..6months to 1_1/2yr

It will take at least six month, sometimes it takes more than a year but you have to wear it atleast for six months

Depending on severity 1 month to 1 year