Your site is live at an address like:
studio.whiteoakmedia.io/site/your-church-name
You'll always see yours at the top left of Studio, next to your church's name. Click it to open your live site in a new tab. Share that link on Facebook, in your bulletin, anywhere.
Want it to be yourchurch.org instead? You can: go to Settings → Your web address, or see Connect your own domain.