If you want to test whether if 2 proportions in a population is the same or not. In order to find the proportions you divide n1 and n2 with N:
Proportion 1 = n1 / N
Proportion 2 = n2 / N
Example, Bob wants to predict the presidental election outcome between Jeb Bush and Bob Iger. He takes a look at the polling where 1000 people have stated who they will vote for.
383 people said they will vote for Jeb Bush (n1)
420 people said they will vote for Bob Iger (n2)
189 people are undecided
N = 1000 (total sample size)
Proportion 1 = 383 / 1000 = 0.383
Proportion 2 = 420 / 1000 = 0.42