Does anyone know about Chickens? Help please?

Question by The unknown: Does anyone know about Chickens? Help please?
Hello. My family and I want to build a chicken coop to get chickens. We live in the Granada Hills area in CA, and I heard that Hens are permitted to keep. I have questions concerning the matter of raising chickens for eggs.
Can you keep a rooster in Granada Hills area? If so, how often will he fertilize the eggs?
I mostly have concrete in my backyard, is concrete bad for chickens when it comes to roaming around? (Don’t worry, the area that I will be using for the coop has lots of dirt, like more than 10 feet long, 6 feet wide.)
I own a pool, will that be dangerous for the chickens? It is fenced off though.
Is it best to get chicks or chickens ready to lay eggs?
What do I do if it rains? What covering (Roof/ceiling) should I use for the chickens?
What should the temperature in the coop be? I heard from a YouTube video that it should be 75 degrees Fahrenheit. Is that true? We get a lot of rain in the Wintertime, so what type of heater should the chickens have? A light bulb?
Where should I look for chickens, online, or a chicken nursery?
What are some popular chickens for Valley climates? Warm, hot weather.
How many chickens should I start off with? Is 3 okay?
How are Rhode Island whites? Are they a good breed of chickens?
I know these are a lot of questions, but I really need help from the smart people of the Yahoo community. Thank you so much for your time and effort in answering all of my long boring questions. Thank you! If I have another question(s) I will post them in the additional info.
Once again, thank you!

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