Q. 1. Those who are ordained online by paying a fee for their priesthood, are such ordinations valid?
A. 1. I assume you are asking this question as a Catholic. First of all, Catholics cannot be ordained in a non-Catholic Church because such an action would be a rejection of your Catholic faith to join another heretical Church.
Secondly, such ordinations are invalid. What is involved in these online ordinations is that you pay a fee in return for a piece of paper that says you are now a member of their priesthood. If you pay a little more, you can also buy the title of "Bishop."
Online ordination are not "apostolic," in direct line with Saint Peter. Nor do their candidates receive any kind of training. This is not the Catholic way of doing things.