I have attached the image of the sailboat I'm designing. I'm struggling to connect the edges of two surfaces, one is trimmed (hull) with a waterplane. How it will be the procedure to connect the edges? because I cannot find the command to show the points of the trimmed surface in the new edge.
In MAXSURF, the best option here would be to not trim the surface, instead align the edge of the surface where you want it to be.
For your deck, you can select the hull surface edge (turn render off to select it) and use Surfaces | Extrude to extrude a new deck surface.
If you do need to trim the edge, you can try selecting the trimmed edge of your hull and using Curve | Fit Curve to Contour. Once you have a curve there, you can extrude it into your deck.
I'm not sure if these two commands are in v20. You should update to or latest version (currently v22.01).
Your third option is to trim the hull to the deck and the deck to the hull. In this case you won't be trying to align your control points.