New Family Sharing account.
I've joined my wife's Family Share Account which has a huge capacity (and cost). How do I close my small iCloud account (and modest cost)?
iPhone X, iOS 14
Though I have not fully understood your question as there is no separate payment plan for iCloud+ for individuals and for a Family.
Remove yourself from a family group
- Go to Settings.
- Tap Family. If you don't see Family, tap your name, then tap Family Sharing.
- Tap your name.
- Tap Stop Using Family Sharing.