Can a person attend college of dentistry when entering as freshman or does the have to wait until after 2 years then transfer?

You cannot enter a college of dentistry as a freshman. Dental schools are postgraduate programs. You must first complete a bachelor's degree (or equivalent) before applying. The specific requirements vary by school, but generally include prerequisite courses in science subjects like biology, chemistry, and organic chemistry. There's no transfer from a two-year program; it's a complete undergraduate degree first, then dental school.