Can you go inside the light house?

You cannot climb the actual tower, but there is a nice visitors center/museum on the lighthouse campus that provides a plethora of interesting information. The park surrounding this great facility is worth making the trip, especially if you have children

No

The tower is not open to the public.

My wife and I honeymooned in Portland in July. No lighthouse access was granted. You could walk the grounds and that was it.

Not that I remember