A. Single tooth or small sectional orthodontics (braces) does exist if you try an orthodontic practoice they may be able to help with advice, expect to pay privately it is not likely that it would be covered by NHS criteria.
The quicker option is veneers/ crowns, often on the adjacent teeth as well. Also expect the crooked tooth to be cut back before it is veneered.
Our practice offers a free initial consultation with a cosmetic dentist to give you a better idea of the best option for your individual case. But please mention the cosmetic guide when booking this consultation.