Pretty much. but, honestly you don't use "many a" too frequently. It's really 'profound' or 'formal' i'm not sure which one but it isnt common and if you used it in a conversation with a native speaker the would think you were wierd. I'd stick to "many" ^^;;;;

"many a" is extremely old-fashioned used in several fantasy computer games. I hate this expression. never use it with people you do not know

many : means alot of something/ persons we use many with plural countable nouns . e.x : how many brothers do you have? how many students are there in your class ?

Alexandre, Many a .....means EACH of a large undefined number. It takes a singular verb. There are many doubts about it == There IS many a doubt about it" Many ......means a large number. It takes a plural verb. Many men are asleep in the deep==Many a man is asleep in the deep.