May I gently correct you here? I made the very same mistake when I got my first chicks. Pullet is the term for a juvenile hen, and cockerel is the word for a juvenile rooster. So in your batch of chicks you may have pullets and cockerels.What are some opinions about starting with chicks vs. pullets for a first timer?
I didn't know which way to start either, so I started with chicks instead of older birds. For me and my situation, chicks turned out to be the best way, because our chicken fever overcame our common sense and we just weren't ready to house older birds. It was a way to get to know their personalities (and yes, you will find that they do have those!) and get into a good solid routine as far as care without being quickly overwhelmed.
That said, you just do what feel comfortable to you. There's so much information here on the forums that sometimes I suffer from information overload. When that happens, I take a step back, look at what I've done that has worked and what I need to do to make things better, then choose the solution that makes the most good old fashioned common sense to me. And some things depend depend on your area too...what works in Arizona doesn't necessarily work well here in frosty Northern Wyoming.
Relax, enjoy the journey. If there was only one way to raise chickens, this entire forum could be read in half an hour! As it is, there are tons of good people here who share what has worked for them, explain what hasn't worked and why, and pointed out what they would change if they could. The Learning Center is a good place to start!