Yes. that is exactly what braces are for!
Normally yes. Depending upon your tooth and jaw alignment, braces can normally be used on patients of permanent dentition age. (sometimes younger ages, depending on jaw.) braces might be not indicated if a jaw surgery may have to be performed to align the upper and lower dentitions and that would be a decision that needs to be coordinated with orthodontist and oral surgeon.
Yes. An orthodontist would best be able to evaluate your situation and advise you accordingly. Sometimes there becomes need to also utilize the services of an oral surgeon as in orthognathic cases. Hope this helps.