My dad is a preacher, A preacher is usually a person who delivers sermons or homilies on religious topic
Do they have sermons?
Most times they do, Less common are preachers who preach on the street which i think it is good you preach what you believe no matter what
The street preachers are scary!
Yeah specially because sometimes they scream and freakout
I had some on my college campus that told me I was going to hell.
hahaha that is not good, The Dominican Order is officially known as the "Order of Preachers"  which is a very important order 
I have not heard of htat