The way to get them is by buying it with primo gems, dust, and events.
You get 60 primo gems a day, you have to wait every month to buy 10 fates with dust (make sure you always have 1250 just in case), and events come and go.
The game is a game of patience. It is perfect for casual gamers, which is the intended audience. This game is not your “grind 6 hours a day Korean MMO.” This game is more “log in every day and do your 30 minutes.”