I would agree with the girls here
It's much safer for your fish, and less work for you to cycle without fish
BUT, if you'd like to use feeder fish... I don't think that's a very good idea since they can carry unwanted disease |: So when you'd introduce your new fish, they may all get sick
So I say, if you want to cycle with fish, buy maybe two, in the case of goldfish, four in the case of small tropicals, but let your tank stand in peace for a week or two before introducing them! In the meantime, you can add fish food, shrimp pieces or some fish meat to the tank to get the cycle going!
When you finally introduce the fish, remember to use some fluid bio filter booster! There are pretty many out there. Many on the forum are using a product called "Stability" I think it was by Seachem labs, and I was using "fluid bio filter medium" by easy life. And I believe both would be very good for your tank while cycling it