I'm so sorry for your dc.
No one should have to put up with that kind of behavior.
You don't need to enroll your dc in a distance-learning school like Penn Foster. We have *oodles* of choices for instructional materials and methods and everything.
Yes, we would need to know whether you would like faith-based materials or not so we can make the best recommendations.
For the practical issues, IL is a great state to homeschool. you don't have to report to anyone or get anyone's permission. What you will want to do is have a plan, and when you're ready, withdraw your dc from school. The law does not require this, but if you don't officially withdraw him, he'll be suspected of being truant, and that will be a bad thing. My strong recommendation is also to join Home School Legal Defense Association (HSLDA)
. Even though hsing is legal, there have been significant issues with school officials in some districts causing grief for hsers, and you just don't want to deal with that.