Hello.
1) For alignment of teeth, You will have to undergo an orthodontic treatment. There are various options available in braces like metallic/ceramic (tooth colored braces) or invisible braces,aligners.
You may opt for other options as well, like, smile designing, dental veneers or dental crowns.
Please visit an orthodontist to know what suits you best.
2) The tooth, (1st Molar) as shown in the photo, is a decayed tooth. You will require a x-ray for diagnosis, and accordingly you may need restoration of the tooth or a root canal.
Please visit a dentist to get yourself examined
Next Steps
Kindly visit us at Dental Galaxy Pune for treatment