Good day, I have stopped family sharing, does it automatically go to single subscription

Not if the subscription was a family subscription. From the article posted above.

What happens to your content when you stop sharing?

When you leave Family Sharing, your Apple ID is removed from the family group and you won't have access to any services shared by your family. This might include an Apple Music family subscription or a shared iCloud storage plan.

Yes it does. See Leave Family Sharing - Apple Support.