Hull boat design doubt

This thread may be relevant. Boat hulls with smoothly curve stems - how to model

How high quality do the surfaces need to be? Will you be using the surfaces only for calculations or also for other purposes?

A simple way to obtain a surface for calculation purposes from a set of curves is to use Patch. Experimenting with the the number of points in each direction and other Patch input parameters may be needed. However Patch will not exaclty follow kinks in curves. Frequently if there are kinks, such as below the rail in your model, the model can be divided into several parts and Patch used on the curves for each part. Be aware that it may be difficult to join the patched surfaces with watertight seams.

Another approach is to define one or more areas with 4 or possibly 3 or 2 boundary curves such that the boundary curves in whole or part are curves in the model. Create a surface using the boundary curves. Then use that surface as the input surface to Patch along with the remainder of the curves inside the boundary.

A third approach is to use Sweep2 with the keel and gunwale curve as rails and stem, station and transom curves as sections.

There is no single method which works for all boat shapes.

But before working on your boat model any more take time to go through the Users Manual, Level 1 Manual and Level 2 Manual which can be found at https://www.rhino3d.com/tutorials