You know the reply box/tab that you write in? On top you will see several icons, one of them is a square with a house on it. If you hover the cursor over that (without clicking) it should say "Insert image". Click it and select "My computer" then select the pictures you want to post...
I believe you have pullets. The pattern on a rooster is usually lighter and finer than the pullets. Perhaps you can see the difference in this picture. The BR roo is on the left, the pullet to the far right (sorry she is only a partial, but it is the best pic I have with young ones together.) These are about 7 weeks old - notice how big the comb is on the roo.