I love the Hornblower series, but my grandpa was an old Geordie sailor, and i grew up sailing on Lake Erie. I'm actually reading my dad's old collection of Hornblower and have loved it. Forrester sometimes goes a bit heavy on the sailing jargon, but they are such excellent adventures. Start with Beat To Quarters and if you like it read them in chronological order.

As for Dune, i have been loving the series as well. My only experience prior to reading them was references in other media and watching the 2021 movie, but they are hands down the best series i have ever read.