The most convenient access to the various attractions of the park is via the town of Lincoln, NH, just off I-95. There are no formal entrances to the state park per se, but merely numerous portions with great hikes (eg The Flume, The Basin, etc).

Sorry; most of the main areas are not handicap accessible. This is an area mainly for hikers, though nice views are accessible from parking turnoffs.

If you want to ride the Tram, that is perfect for views. If you want a short hike, park at parking lot for Echo Lake, cross the street and hike to Artist’s Bluff. 30 minute hike to beautiful view of the Notch! Not sure about your GPS settings. Put in Echo Lake State Park or Cannon Mountain Ski Area for Tram.

There is no charge, but in nice weather, I expect the parking areas can fill up pretty early.

Nothing specific, just going up the trails they have there. There's one main trail, and one or two side trails you'll see as you go along.

It is not flat - mainly sloping. We were there in winter when there was snow/ice on the ground, which was a challenge. But in dry weather it is not difficult. I would recommend folks with balance or walking issues use a walking stick.

I don’t think so.