Right along the walkway that parallels Georgia Tavern Rd ( the main roadway to the park) or from the short trail leading from the auxiliary parking lot just beyond the main entrance.

Not that I am aware of. But give a call and find out.

Any of the parking lots connect to the path. 5 miles long goes around reservoir

If you park at the small parking lot on Georgia tavern road and walk to the area where the road goes over the reservoir, you may be able to see it rise over the trees. I am not sure if the parks open the parking lots before the sun rises or not.

A direct call would be best. But I do believe you should have access around main building.

I have been there many times and there are areas where a wheel chair could sit close to the water like at the Visitor center on Windler Road. I just don't know anything about fishing or where it is allowed. If you can, Google the Manasquan Reservoir and call the info number. They would tell you what is available. They list the park as being handicapped accessible.

Not the whole thing, no. There are parts of the trail that you could manage, but much of it is gravel. There are a couple of connected paths near the visitor's center parking lots that are paved too, so you could manage a short walk with the wheelchair.