How should I handle my child being bullied at school?

Teach your child to fight its the only way im being honest with you my son who was 11 at the time was bullied by this kid from his school who i later found out lived 4 blocks where we lived. I went to the school reported the asst principal said they couldn’t do anything without proof i said u have cameras they said they delete at the end of the day. I went to the board of education i called a lawyer, newspaper even went down to police station they told me they aren’t going to get involved unless something serious happens that he isnt going to ruin the bullies life like wtf i felt so hopeless no one would help me so i took my kid to boxing told him he has to fight i tried everything i could as a Parent i even talked to the kids mom she said it was my kid who bullying her son that her kid wouldnt do that. Later i found out after it was over thst the kids dad is very abusive to the kid they ended up moving and taking the kid outta school so after all this shit we went through they decided to vanish my son is okay now. This happened in Columbus ga

Talk to the principal and the parents.

I can’t believe this is a question