If you use Google to search for
Mathematica Umbilic torus
then hopefully one of the results you should see is a couple of pages from “Mathematica by Example” and on page 84 that shows one method of plotting what you are looking for.
If you have access to a library with a copy of the book or you can find a new or used copy to buy that might be even better.
The parameters “u” and “v” are local to the parametric plot, so it does not make sense to try and vary those. But you can vary just about everything else in this plot, for example: