It's very typical for pilots to be required for all entrance and egress from harbors, much more than the initial pushaway and turning but for quite a long distance through the channel.
Pilots always, for most harbours - they are extremely well versed on local tides and currents and essential for many river mouths and locations with large tidal swings.
Tugs - quite often, but not always - depends on the currents, ship weight, and time of day.
Depends on the navigational requirements. Indirect towing using tugs as an extended rudder are sometimes used. Although I think it is more common in Europe which has a more modern tug fleet.