Ok, that was a good laugh... yes, she's asking about Guinea Fowl... not Guinea Pigs. But, she did just say Guineas so I can understand the confusion.
Anyway, I'd suggest using the Search feature at the top of the page and type in "Guineas" - you'll get lots of great info on them from different threads.
If you want them to come back to the chicken coop to roost each night you will want to keep them locked in there for at least 2 months before letting them free range. Then, some people say to just let part of them out to free range while keeping some others locked in the run so that the free ranging ones will stay close by and come back. I just let mine all out at the same time with my chickens (who they have been raised with) and they always stay close BUT... mine are only a couple of months old so I don't have good long-term experience yet.