My last name is Herskowitz. I was told that I am a Kohan. After reading Kohan names are Cohen and Katz. Am I truly a Kohan?
The definition of a Kohain is someone whos father is a kohain and so forth dating back to Aharon the brother of Moses. There were three families in our synagogue named Cohen. One was a Kohain, one was a Levite, and one was a Yisrael. The secular family name does not necessarily mean anything. Indeed, there are people with Jewish family names who are not Jewish.
Thus, unless you can trace back the identity through your father and his father etc. there is no way to know about your status.