Hoboken is one square mile. Almost everywhere worth going is reachable on foot in under fifteen minutes from the Terminal. The Hudson-Bergen Light Rail runs north along the waterfront and is useful for reaching Jersey City or Weehawken. Citi Bike has a small footprint here; the city's own Hudson Bike Share is bigger and easier.
Taxis cluster near the Terminal. Ride-shares (Uber, Lyft) are everywhere. If you have a car, expect to circle and search; consider a paid garage rather than the metered street parking, which is policed aggressively.