Choosing a Fly Rod for Saltwater
Whether you are starting out from scratch or coming from years of freshwater fly fishing, selecting the right fly rod for saltwater is a matter of what fish you want to catch and where you plan to go fishing the most. You don't need lots of fishing experience but it does help to give us at minimum a general idea like "I saw somebody catching an awesome tarpon, now I want to catch those" and we will go from there.
You can start with either of those points, for example if you know you want to go to the Bahamas because your significant other will also enjoy that trip (we hear this a lot), then you can at least start to narrow down the gear you will need. Now, do you want to stalk bonefish on the flats? Chase tarpon around little islands? Go after a sailfish offshore? Three very different rod and reel setups, not to mention line and flies.
Bonefish are one of the most popular fish to catch on a fly, and rightly so. They are fun to pursue and many times you can do so on foot. Most experts would suggest either a 7 or 8 weight rod and reel combo spooled with an appropriate flats-oriented line (Rio FlatsPro is very popular) and many companies actually make specific line for targeting bonefish to make your decision even easier. Really the hardest part with bonefish (and a few other species) is the never-ending debate over which flies work the best.