Hi, Welcome to OpenStreetMap.
I've reinstated the Public Right of Way as it is still a highway no matter its state of repair. There looks like there is a gap in the central crash barrier to allow for crossing.

 What you could do is contact Suffolk County Council and complain about the state of repair of the highway.

Levington Heath, both sides of the A14, is Open Access Land, so you are allowed open access on foot to the whole area; it's on the Ordnance Survey map.

Regards Bernard.