You likely already know the answer after all this time, so I'm putting a reply here in case someone else comes across the question while shopping. It doesn't come with a gas dryer install kit by default, that's an extra, so if someone included it for you, they won't necessarily include it for anyone else.
For the steam part, you simply need a short piece of hosing. This ships with a Y fitting to split the cold water faucet into two and a short (12" or less) hose piece in case you need to use that from the cold water feed and then put the Y splitter at the end, but that still won't be enough to reach the inlet on the dryer, which is on the very bottom right (when looking from the back). So you'll need a piece of hose that's male on one side, female on the other, and will get you the rest of the way to the floor level to reach the inlet on the dryer. No specific part needed, although as with anything, it's always good to use the steel lines to help prevent a rupture in the line. the piece of hose they give with it is a standard rubber hose section, not braided metal sheathing or anything.