Is it correct to have a space before a question mark? Like: "How are you ?" I have seen a lot of sentences with space right before the question mark and lots of sentences with the question mark right after the last word. So, I do not know which one is more correct and why: "How are you ?" "How are you?"

Any form of punctuation comes right after the end of a sentence. You wouldn't leave a space after a period (That puppy is soft .) it'll just look weird, and the same thing with an exclamation point (The puppy is so cute !). So if you want to have better sentence structure put the question mark right after the end of your question (Where did you get the puppy?). Hopefully this helps.

No

No you have to do this how are you?