Make field content as exposed filter dropdown
your question isn't 100% clear but it sounds like you want to display the nodes in a view and want to filter them with an exposed "brand" dropdown? 
I also assume your "brand" field is a term reference to a vocabulary.

Create a view for the nodes and add a filter for "Content: Has taxonomy term" and select your "brand" vocabulary, "dropdown" as the filter type and "expose this filter".