"I am going to take a break."
Translation:Je vais faire une pause.
This is rather idiomatic, because the French use "avoir" with nouns for a number of experiences, but then there is no article: avoir faim/soif/peur/honte...
But they don't use "avoir une pause" if this means "take a break".
"Avoir une pause" rather means to be entitled to a break, not to actually take it.