ReadEdenHow to read Dune without getting lost in dozens of books
The shortest useful answer
Start with Dune. If you want to continue, read Frank Herbert's books in publication order: Dune Messiah, Children of Dune, God Emperor of Dune, Heretics of Dune and Chapterhouse: Dune.
Do not begin with the earliest event
The expanded chronology contains prequels set long before Paul Atreides. They were written later by Brian Herbert and Kevin J. Anderson. Chronological order places additional explanations before the novel that originally introduced the world.
The first book can stand alone
Dune has its own arc. You do not need to commit to six books before opening it. Continue to Dune Messiah if you want to see the consequences of the victory rather than simply another version of the first journey.
After Chapterhouse
Frank Herbert died before writing another planned volume. Later books continue and expand the universe through different authorship and a different creative period. Treat that as a new decision, not as an automatic seventh step.