Hello and welcome
A few questions, What do you mean when you say cage? Any pictures?
Is there an area that provides shelter from rain and wind?
Knowing your location would also be helpful.
Any plans to get more? Guineas do best in bigger groups, 10+.
Without more information I’d say it’s likely they will keep coming back to the cage once let out.
You can slowly release one at a time over the next week so they don’t travel far. Example: day 1-2 let out only one guinea. Day 3-4 let out two guineas. By day 5 you could let them all out with supervision. Herding them back towards the cage if they go farther then you want them to. And just keep that up for a few weeks.
If you are consistent they are very easy to train.