I found a paddle boat on my lake.It has been there for a long time so I deceided to bring it home.The steering is done by a metal bar that turns right or left.The bar does not turn and is locked.I looked underneath and there were not obstructions.Sprayed W-D 40 through out the steering line and still nothing,any suggestions

It's probably rusted through so much that the joints have kind of fused together. At that point, any lubrication wouldn't work. You might as well replace the entire steering mechanism.

Or does the rudder turn independently of the tiller?