There is a special colorless polish u buy in the pharmacy to apply to ur nails every morning. Once u apply the ploish try biting ur nails,the taste is HORRIBLE. U will stop biting ur nails for good!! It’s a bit annoying at first since u r so itchy to bite ur nails. SO u’ll keep tasting this and that will be the end of the bad habit.
For something less severe, why not try an expensive nail hardner. U will physically not be ABLE to bite ur nails.
It’s really good of u to try and stop this habit bec nails are a dangerous thing to leave around or spit out of ur mouth once u chew it off.