I told my dad to register himself to get a vaccine since i don't trust the vaccine know he is mad at me?

I really don't want to register him because i don't want him to blame me if something happens. So i told him to register himself but he doesn't know much about computers but i did give him some phone numbers to the local pharmacies if he really wants it so bad. Know he is pissed at me. Why is he pissed at me?