Why don’t you teach your child yourself? Any parent who is acquainted with the child’s current point of development with regard to education should be able to do that, at least to some useful extent - and to probably a superior extent than public education can usually do.
Yes, any parent who went through K-12 knows that stuff better than any student. You have years of life. Get the workbooks - Spectrum Math is good. You just need straightforward stuff. You do not have to match what the public schools are doing to homeschool.