Yes you will want to walk the ocean trail and at low tide also walk out to the island and walk the trail on the island!

We were only walking so did not pay much attention to the bike trails but there are plenty in the area and maps and info are available from the visitor centre.

No. Ocean path is in Bar Harbor along the waterfront. Ocean trail is in Arcadia.

Dogs on leash are allowed. The path is narrow but flat so depending on the size of the scooter, it may be able to fit. The issue is the curb to get onto the path and the access from Sand Beach has steps. I believe there is a handicap access from the parking lot near Thunder Rock. If someone can help get the scooter up on the curb, you can park anywhere on the side of the road.

The trail itself is flat and easy for anybody. The parts that jut off toward ocean are uneven and rocky but the views are just as beautiful from the trail. You can also drive to any part of this trail and park in right lane at most areas, so parking, stopping, getting out and driving again is easy.

yes they are

They are not the same. Shore Path is in Bar Harbor, in town. You start and end in downtown. Ocean Trail is inside Acadia National Park. It runs between Sand Beach and Other Point.

I'm not sure of the exact address. However, if you get a map of Acadia, it is very easy to find. It essentially starts near sand beach and goes past Thunder Hole (there are signs for those upon entering the park). I think it is called Ocean Path on some of the maps.