Son starting high school but has seizures

My son has been home schooled his whole life a is starting High school at a public school this year (don't ask why) he has an issue with seizures and has at least 3 a day.... He's scared to go because he usually pees and poos himself when he has a seizure. I was gonna give him extra clothes to bring but he's still scared about what the other kids will think. Does anyone have kids who have seizures or do you have seizures in school because I need advice.

Edit: Way ahead of you guys. We've already met with the school for his 504. He's just nervous about the social part. The school guidance counselor told me to make sure he gas extra clothes for when accidents happen. She also recommended a diaper just in case so it will keep people from knowing but I'm not even gonna bring that up to my son. That's Dead on arrival I already know. He's just so nervous.