
Hi and Welcome to the wonderful world of chickens.
It depends on the breed. Some genders are easier to identify than others. People claim that you can tell this or that and know that its a hen or rooster. I just want till it lays an egg or crows. Sometimes you can tell by the comb. Some breeds if they are roosters will grow their combs early and you can tell pretty quick if its a hen or rooster.
I would not feed your chicks anything other than their chick feed for the first 10-20 weeks. Reason I say this is because they are growing, anything that you introduce to them food wise will be taking away or diluting the nutrition that they need to be getting from their feed. Personally I do not allow my chicks to eat anything other than their chick starter feed for at least the first 10 weeks. At that point I can allow them some free range time. But I don't give treats or anything while they are in this crucial growing phase.
I allow my flock free range everyday in both warmer and colder months. The only times that I lock them in their pen is when we have severe weather coming or bird flu scare. In the spring months we can get some nasty storms with large hail. During these periods I absolutely keep my flock in the shelter and safety of their coops and covered pens.
Its really a judgement call when it comes to supplemental heat during the colder months. chickens come factory installed with down coats and are able to regulate their body temperatures quite well. I think that the biggest mistake that chicken keepers make is judging their comfort by our comfort levels. Chickens have an internal body temperature of about 107 degrees F. They can acclimate to the cold weather quite well. If you get to something like -20 F you might want to consider a radiant heat plate. Heat lamps are dangerous due to the possibility of coop or barn fires they many time cause.
If their coops are kept too warm in can actually be dangerous for them. If they are kept too warm and they get used to it they can actually die if there is something like a power outage turn off their heat source. Additionally, if they are kept too warm sometimes they will not want to leave the coop in search of food or water. Keeping them too warm can disturb their natural ability to acclimate to the colder temperatures naturally. If anything all you want to do is just take the edge off not so much blast them with a high heat source.
I have never given my girls supplemental heat. They have been through 10 winters now and have come through all of them just fine. They only thing that I do for my girls as far a winter preparedness goes is to wrap their pen with construction grade plastic. This acts as a wind break and keeps the rain and snow out of their pens. The key for over wintering a flock is to be sure to keep their digs clean and dry, they do the rest. I have found the the less I intervene the better they do.
I hope that this helps you.
Pleased to meet you and Welcome to the Coop!