Watercolor paper is the one single product that we use that  impacts our success or disappointment while trying to learn watercolor techniques.  Regardless of your level of experience, the paper you use will make a  difference in progress and in the finished product.

From Carrie Luc at the 'Watercolor Misfit' here is an example of how three grades of paper look when they have been painted with identical subjects.

My favorite remains Arches, but here is another video from Carrie Luc that compares the papers by brand.  This breaks away from using 'academy' grade or 'professional' grade and get down to papers that are commonly used . . . with a surprise ending