My teeth are yellow and not straight. How can I get perfect teeth? (Photo)

Without an exam it's difficult to give you ideal treatment.  Usually, straight teeth are accomplished by orthodontic treatment.  If you want them to be whiter, you can look into teeth whitening options at your dental office.  If your teeth don't become as white as you would like them to, another option would be to do porcelain veneers to get them whiter than a professional teeth whitening visit.

Hi:Depending on how white your teeth to be, you have two main options:1.  Invisalign and whitening2.  Porcelain veneers to make your teeth whiter beyond what can be accomplished by whitening.Best,Dr. Maddahi

Usually crooked teeth are straightened with orthodontic treatment and yellow teeth are whitened with a whitening procedure. From the limited information I see in your photo, it looks like porcelain veneers could both whiten and give your teeth a straight appearance. You may still need orthodontic correction before any veneers are done. You should go visit an experienced cosmetic dentist for an evaluation.