Selecting rows having substring in a column

Using postgres-11.1 here. My SQL knowledge needs expanding and my web
searches have not found a satisfactory answer. I hope to learn the correct
approach here.

A table (Fishes) has an attribute column stream_trib with values such as
     Small Creek trib to Winding River
     Roaring River trib to Winding River
and I want to find all rows containing Winding River in that column.

The postgres substring function takes as arguments the substring, starting
position, and length. In my table the staring position varies although the
length remains constant.

I need to learn how to construct a SELECT statement that returns the set of
rows containing the substring 'Winding River'. A pointer to references would
be great; so would a detailed lesson in handling this and similar queries.

Regards,

Rich