This pattern is from the Hat Not Hate campaign, which distributes blue hats each year to schools, as part of a program to raise awareness and stand up to bullying.

On the Hat Not Hate website, there is a tab for Patterns. This hat is under the label “HNH Patterns 2020”. This opens a “lookbook” of a number of patterns.
Direct link to lookbook: Hat Not Hate 2020 Look Book

Pattern says “one skein” of suggested yarn.

Very stretchy, and should fit child to adult

The picture is of the hat I made; I added stripes. The pattern is for a plain one-color hat.