Help me understand Family Sharing

I've read the stuff on Apple's site and searched through some questions here. Maybe someone can summarize for me.

All I want to do is enable Family Sharing so that me and my wife can have the $14.99 family plan on Apple Music. I don't want to share playlists from our existing iTunes libraries or anything like that. I don't really even want to share app purchases. Is there a way to set this up but keep all our stuff separate except for this Apple Music subscription?

This will especially become important when I decide to add my kids to the account down the road. I don't want them to have full access to everything I have on my devices.

Thanks in advance!