"We are now having a rest."
Translation:Мы сейчас отдыхаем.
Since Russian doesn't distinguish between simple present and present continuous the way English does, "сейчас" here just helps to stress that what we're doing right now is resting/relaxing, as opposed to, for instance, stating that we rest/relax regularly or habitually. Contrast with e.g. "Мы отдыхаем каждую субботу" ("We relax every Saturday"). It's not required, though, and may be obvious from context.
I suspect that would require future tense, but maybe a native Russian speaker can correct me here...