How likely is it that i got oral hpv from kissing a prostitute? does that happen often? and whys reading about that topic is confusing like no one can be sure of anything. some doctors say yes other say its rare if it ever happens?

Saliva contains enzymes that reduce infectivity potential for may types of germs, this one included. I wonder if you ever notice a n animal/dog licking its wounds to help heal them. Its natural to them & helps.

It is not confusing. Why a person gets an infection depends on many factors including the persons immune system so it can not be precisely predicted. The likelihood of your HPV increases for the prostitute may have had multiple exposures or have an active lesion.