Apple ID Family sharing

Originally when we set up our phones we were advised to use one Apple ID for my husband, my phone and my kids phones. I now see that Family sharing is available. I would love To be able to use the shared calendar features family sharing offers. But am unsure if we should each have our own Apple ID? Or since we set it up this way should we all stay with the same ONE Apple ID? Don't want to lose all of the apps that we are currently sharing Thank you!