Hi Prateekk! We only use the word "no" in both cases and we use it as follows: "No tengo elección" (I have no choice) "Eso no es justo" (That's not fair) "¿Sí o no?" (Yes or not?) "No puedo" (I can't) "No lo sé" (I don't know) "¿No es eso un gato?" (Isn't that a cat) We also use it in question tags: "Hoy es lunes ¿no?" (Today is monday, isn't it?) We also can say: "Hoy es lunes ¿verdad/cierto?" "Ella estuvo allí ¿no?" (She's was there, wasn't she?) I hope it helps.

It's all 'no' in Spanish.