Most caregivers, if they get paid at all it is by those they are caring for, your dad. A caregiver agreement is best to be prepared by an elder law attorney. And care has to be medically necessary as determined by the doctor. There is much info on this site, most often asked question on this site. Search function will help.
https://www.agingcare.com/articles/how-to-get-paid-for-being-a-caregiver-135476.htm