Catholic traditions/Tradition teach of some people being created / some not, and a whole bunch of different species* (God, humans, various angel classes, etc). Besides God, all other persons had a time where they did not exist and then when they did. Also in Catholic tradition, some persons have the right to choose, and some do not.
LDS beliefs are different. A person is a person, no different species*. All existed before this world was made, and before any recording of time (there's no time they didn't exist). All have the right to choose. It's actually super simple.
@Jonah, if you want to engage in conversation here, that's always welcome.
*"Species" = is a poor fitting word here, but it's the best I have.