I have a floor with a texture that simulates the sea and I should create the waves, how can I do?

You could tesselate the ocean floor and then in real time alter the heights of each vertex in a sine wave like fashion.
Depending upon the number of verticies you use this could be quite acceptable with any rendering technique.
The best thing to do is try it and see what performance you get rather than worrying about how to optimise it before you have even tested the basics.

Thank you for responding.
I used to create the floor, “glutsolidcube” which should already be tessellated is correct? so what should I do now?
thanks again