A rampage like that would make anyone feel unsafe. I don’t know if your stepdad is “crazy,” but I do know that his behavior was out of control. I hope you are talking to your mother about what happened and what she is doing about it.
No kid deserves to feel put down and scared in her own home. This family needs support and counseling if it is to be a happy one.
If your mom won’t make it clear to your stepdad that violence and insults won’t be tolerated, she may be as scared as you are. In that case, it may be helpful for you to talk to your school counselor or another trusted adult about how to help your mom.
I wish you well.