A quote is what someone says, either to you or to someone else. It can be from a person or a company. Usually, it is written like this: "It is hot today," said Jimmy Smith.
Or, it can be written like this: Jimmy Smith said it was hot.
The best quote you have should be the one you use first.
Make sure you have the person's full name, and that it is spelled correctly. Tell us why you are speaking to that person. "It is hot today," said Jimmy Smith, who regularly surfs at the beach. "I don't see why we can't swim just because there is no lifeguard."
When translating quotes from one language to another, be sure to put them into the tone of language the person used.
However, do not embarrass the person you are quoting. If their English is not good, it is quite alright to tidy it up for them. This might change if you go into journalism professionally, but for now treat people the way you would wish to be treated.
We never write quotes exactly the way that someone says them, unless they are from a formal speech or a written answer. In the old days, journalists seldom used recording equipment and so would jot down notes on what people said.
Never add anything to a quote. For example, if all you have is "It is hot today" from Jimmy Smith, you cannot say "I'm so hot today, I can hardly breathe," said Jimmy Smith.
But you can leave words out: "it was hot," said Jimmy Smith.
Don't be tempted to add adverbs to your copy. "It was hot," said Jimmy Smith exhaustedly. The copy editor will just take it out.
Unless you are writing in a Q and A format, you shouldn't have to tell the reader what you asked. You would not say: When asked about the weather, Jimmy Smith said, "It is hot." That quote adds nothing to your story. You as the writer should put that in as narrative: Jimmy Smith of Best School won the 300m hurdles for boys in the stifling heat on Saturday.
Quotes should be interesting, surprising, exciting or informative. Do not use quotes to tell us things we would already know. This especially happens in sports stories, when the athletes say the same thing "I am so happy to have won."
If you keep on getting the same answers, change your questions. Often reporters go out to interview a number of people at a function. We work on having three quotes per story, and we work on a 3 to 1 ratio of quotes, so generally we will speak to nine people to get three good quotes. For example, covering the protests in Hong Kong, most people interviewed will just repeat the slogans. This does not give readers any more information than they would already have from the narrative. It is your job as a reporter to find something interesting.
When doing interviews, do not write the story as one, long, quote. Much of what someone says can easily be summarised down to a few short, clear sentences, and then the quotes you choose to use will shine.