To answer your question, yes it boards from the same place as domestic flights. Same TSA process as domestic flights. No extra checks (on the departing EWR side) other than a passport being required rather than a drivers license.

Double check - airlines may have slightly different boarding or checked bag timelines for international. But otherwise you don’t need to add much extra time over any other flight you would take out of EWR. It’s not much different than flying to Denver.