Niel summarizes your solution with brevity. You may wish to familiarize yourself with some of the details before making a decision. Note that if you leave the family group you lose access to items arising from that sharing and there are restrictions to re-joining groups.
Leave Family Sharing - Apple Support
Legal - Apple Media Services - Apple
D. "You can only belong to one Family at a time, and may join any Family no more than twice per year. You can change the Apple ID you associate with a Family no more than once every 90 days. All Family members must share the same Home Country."
September 16, 2021
From: How to share purchases with your family - How to share purchases with your family - Apple Support
"When you turn on purchase sharing, everyone in your family gets access to apps, music, movies, TV shows, and books that family members buy. The family organizer is billed for family members' purchases"
The second phrase is a bit over-simplified because others can still pay for their own items, they just have to use personal account balance to do so. Turning on purchase sharing simply activates the feature whereby if a family member does not have adequate personal balance to pay for something then the organizer's payment method (e.g., credit card) will be charged.
Read the document for the link to "learn how purchases are billed if a family member has Apple ID balance"
Add money to your Apple Account balance - Apple Support