CNAs are a "higher" level of certification. Most states don't require caregivers to have certifications. In these states, caregivers can work in home health or in assisted living without a certification, but working in a nursing home or hospital requires at least a CNA license.
In states that do have Caregiver certifications, the exact differences depend on your state. For example, assisted living facilities in Arizona have Caregiver roles that require Caregiver certifications (CNAs cannot work in these roles, but the facility may have a CNA role as well). However, CNAs are allowed to work in nursing homes whereas Certified Caregivers can't.