It is used when you want to emphasize a negative sentence. So, as you can see, there are 2 elements: 1. Negative sentence 2. Emphasis For example: a) I don't like this food at all. (De verdad no me gusta esta comida) b) He hasn't done his work at all. (No hecho nada de su trabajo!) c) I won't be going to England at all next year. (No iré a Inglaterra en absoluto el próximo año) As you can see, you can translate it differently depending on the sentence or the way you want to emphasize it. You can use it in different tenses as well (past, present or future), but it has to be a negative sentence. In Spanish, it may be translated as "del todo, en absoluto, en nada, para nada, en modo alguno" etc., depending on how you word your sentence or the emphasis you wanna give. A similar word to "at all" is "whatsoever".

(used for emphasis) in any way; to any extent. "I don't like him at all"

Yes, it is used to emphasize something. "I don't like this food" is emphasized if you say "I don't like this food at all". It's like the difference between "last" and "very last": - He was the last to arrive. - He was the very last to arrive. In both cases, he was the last person to arrive, but the second one has more emphasis.

Thanks for your answer!

as i know, it is use at the end of "not" sentences. "...not...at all"