Custom field to registration page Palm open edx tutor 16.1.7

Hi,

I would like to add some Custom Fields to the Registration Page, but before that I would like to know how exactly do this in open Edx tutor 16.1.7, which files have to be modify, where are the location of this files or any information about this, please for dummies :sweat_smile: because I was reading a lot but I didn’t understand well how to exactly do.