Many treatments. There is no best way.
Varies. There are multiple ways to treat warts and they respond to all of them including freezing, acid, burning, prescription creams, or laser. If it only one wart burning or electrosurgery is very effective. For extensive warts medication is often better to al least decrease the number of warts to a manageable level.
No best. There are many treatments including topical acids, freezing laser, surgical removal.